Method for transmitting and receiving signals in wireless LAN system and apparatus therefor

ABSTRACT

The present specification relates to a method for transmitting and receiving signals in a wireless local area network (WLAN) system and an apparatus therefor, the method comprising the steps of: generating a training sub-field consisting of a certain number of orthogonal frequency division multiplexing (OFDM) symbols; and transmitting, to a second STA, a signal including a header field and the training sub-field, wherein the transmitted signal is repeatedly transmitted T times (where T is a natural number) on the basis of information indicated by the header field after a data field.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is the National Stage filing under 35 U.S.C. 371 ofInternational Application No. PCT/KR2018/004128, filed on Apr. 9, 2018,which claims the benefit of U.S. Provisional Application No. 62/531,307,filed on Jul. 11, 2017, 62/535,240, filed on Jul. 21, 2017, 62/550,717,filed on Aug. 28, 2017, 62/552,394, filed on Aug. 31, 2017, and62/560,199, filed on Sep. 19, 2017, the contents of which are all herebyincorporated by reference herein in their entireties.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a method for transmitting and receivingsignals by a station in a wireless LAN system and an apparatus for themethod.

More specifically, the descriptions given below are related to a methodfor a station operating in the Orthogonal Frequency DivisionMultiplexing (OFDM) mode to transmit and receive signals including atraining field and an apparatus for the method.

Related Art

A standard for the wireless LAN technology is being developed as anInstitute of Electrical and Electronics Engineers (IEEE) 802.11standard. IEEE 802.11a and b use an unlicensed band in 2.4. GHz or 5GHz. And, IEEE 802.11b provides a transmission rate of 11 Mbps, and IEEE802.11a provides a transmission rate of 54 Mbps. And, IEEE 802.11gprovides a transmission rate of 54 Mbps by applying orthogonalfrequency-division multiplexing (OFDM). IEEE 802.11n provides atransmission rate of 300 Mbps on 4 spatial streams by applying multipleinput multiple output-OFDM (MIMO-OFDM). The IEEE 802.11n supports achannel bandwidth of up to 40 MHz, and, in this case, the IEEE 802.11nprovides a transmission rate of 600 Mbps.

The above-described wireless LAN (WLAN) standard was previously definedas the IEEE 802.11ac standard, which uses a maximum bandwidth of 160MHz, supports 8 spatial streams, and supports a maximum rate of 1Gbit/s. And, discussions are now being made on the IEEE 802.11axstandardization.

Meanwhile, the IEEE 802.11ad system regulates a capability enhancementfor an ultra-high speed throughput in a 60 GHz band, and, for the firsttime, in the above-described IEEE 802.11ad system, discussions are beingmade on an IEEE 802.11ay for adopting channel bonding and MIMOtechniques.

SUMMARY OF THE INVENTION

The present invention provides a method for a station operating in theOFDM mode to transmit and receive signals including a training field andan apparatus for the method.

To solve the problem above, a method for transmitting signals from afirst station (STA) to a second STA in a WLAN system according to oneaspect of the present invention comprises generating a training subfieldconfigured of/including a predetermined number of Orthogonal FrequencyDivision Multiplexing (OFDM) symbols; and transmitting a signalincluding a header field and the training subfield to the second STA,wherein the transmitted signal includes the training subfield, whereinthe training subfield is transmitted repeatedly T times after a datafield based on information indicated by/included in the header field,wherein T is a natural number.

To solve the problem above, a station apparatus for transmitting signalsin a WLAN system according to another aspect of the present inventioncomprises a transceiver having one or more Radio Frequency (RF) chainsand transmitting and receiving signals to and from other stationapparatus; and a processor being coupled to the transceiver andprocessing signals transmitted and received to and from the otherstation apparatus, wherein the processor is configured to generate atraining subfield configured of/including a predetermined number ofOrthogonal Frequency Division Multiplexing (OFDM) symbols; and transmita signal including a header field and the training subfield to thesecond STA, wherein the transmitted signal includes the trainingsubfield, wherein the training subfield is transmitted repeatedly Ttimes after a data field based on information indicated by/included inthe header field, wherein T is a natural number.

In the composition above, the training subfield may be configured foreach space-time stream.

At this time, the training subfield per space-time stream may beconfigured by using/based on a basic training subfield per space-timestream configured of M (where M is a natural number) OFDM symbols basedon information indicated by a header field based on a rule determined bythe total number of space-time streams.

As one specific example, when the basic training subfield per space-timestream is configured of/includes 1 OFDM symbol based on the informationindicated by/included in the header field, the T may be 4; when thebasic training subfield per space-time stream is configured of/includes2 OFDM symbols based on the information indicated by/included in theheader field, the T may be 2; and when the basic training subfield perspace-time stream is configured of/includes 4 OFDM symbols based on theinformation indicated by/included in the header field, the T may be 1.

Also, one OFDM symbol included in the one, two, or four OFDM symbols mayinclude a guard interval with a length of 72.72 ns or cyclic prefix(CP).

In the description above, the header field may include an EnhancedDirectional Multi Gigabit (EDMG) training subfield sequence length fieldwhich indicates/including information on OFDM symbol length of the basictraining subfield per space-time stream.

At this time, when the EDMG training subfield sequence length fieldindicates 0, the basic training subfield per space-time stream may beconfigured of two OFDM symbols, and the T may be 2; when the EDMGtraining subfield sequence length field indicates 1, the basic trainingsubfield per space-time stream may be configured of four OFDM symbols,and the T may be 1; and when the EDMG training subfield sequence lengthfield indicates 2, the basic training subfield per space-time stream maybe configured of one OFDM symbol, and the T may be 4.

To solve the problem above, a method for a first STA to receive signalsfrom a second STA in a WLAN system according to yet another aspect ofthe present invention comprises receiving a header field included in atransmitted signal; and receiving the signal by switching processingbetween a data field and a training field during a period within aperiod during which the signal is transmitted, wherein the trainingsubfield is transmitted repeatedly T times after a data field based onthe information indicated by/included in the header field during theperiod, wherein the training subfield is configured of/includes apredetermined number of Orthogonal Frequency Division Multiplexing(OFDM) symbols, wherein the T is a natural number.

To solve the problem above, a station apparatus for receiving signals ina WLAN system according to still another aspect of the present inventioncomprises a transceiver having one or more Radio Frequency (RF) chainsand transmitting and receiving signals to and from other stationapparatus; and a processor being coupled to the transceiver andprocessing signals transmitted and received to and from the otherstation apparatus, wherein the processor is configured to receive aheader field included in a transmitted signal; and receive the signal byswitching processing between a data field and a training field during aperiod within a period during which the signal is transmitted, whereinthe training subfield is transmitted repeatedly T times after a datafield based on the information indicated by/included in the header fieldduring the period, wherein the training subfield is configuredof/includes a predetermined number of Orthogonal Frequency DivisionMultiplexing (OFDM) symbols, wherein the T is a natural number.

The effect that can be obtained from the present invention is notlimited to the above-described effects and the other effects will beunderstood by those skilled in the art from the following description.

Through the composition as described above, a station operating in theOFDM mode according to the present invention may transmit and receivesignals including a training field.

In particular, according to the present invention, a station maytransmit and receive signals including a training field of the OFDM modewhich may be aligned with a training field structure of the SC mode.

The effect that can be obtained from the present invention is notlimited to the above-described effects and the other effects will beunderstood by those skilled in the art from the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

The appended drawings of this specification are presented to provide afurther understanding of the present invention and are incorporated inand constitute a part of this application, illustrate embodiments of theinvention and serve to explain the principle of the invention along withthe description of the present invention.

FIG. 1 is a diagram showing an exemplary configuration of a wireless LAN(WLAN) system.

FIG. 2 is a diagram showing another exemplary configuration of awireless LAN (WLAN) system.

FIG. 3 is a diagram describing a channel in a 60 GHz band for describinga channel bonding operation according to an exemplary embodiment of thepresent invention.

FIG. 4 is a diagram describing a basic method for performing channelbonding in a wireless LAN (WLAN) system.

FIG. 5 is a diagram describing a configuration of a beacon interval.

FIG. 6 is a diagram describing a physical configuration of a legacyradio frame.

FIG. 7 and FIG. 8 are diagrams describing a configuration of a headerfield of the radio frame shown in FIG. 6.

FIG. 9 is a diagram showing a PPDU structure that can be applied to thepresent invention.

FIG. 10 is a diagram showing a simple PPDU structure that can be appliedto the present invention.

FIGS. 11 to 30 illustrate an EDMG-CEF sequence or a training sequenceper space-time stream which may be applied to the present invention.

FIG. 31 illustrates a TRN subfield structure corresponding to one OFDMsymbol.

FIGS. 32 and 33 illustrate a TRN subfield structure corresponding twoOFDM symbols.

FIG. 34 illustrates a TRN subfield structure corresponding to three OFDMsymbols.

FIGS. 35 and 36 illustrate a TRN subfield structure corresponding tofour OFDM symbols.

FIG. 37 illustrates a TRN subfield structure corresponding to five OFDMsymbols.

FIG. 38 illustrates a TRN subfield structure corresponding to six OFDMsymbols.

FIG. 39 illustrates a method for transmitting signals including a TRNfield according to one embodiment of the present invention.

FIG. 40 is a diagram illustrating a device for implementing theabove-described method.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

Hereinafter, the preferred embodiment of the present invention will bedescribed in detail with reference to the appended drawings. Thedetailed description that will hereinafter be disclosed along with theappended drawings will only be provided to describe an exemplaryembodiment of the present invention. And, therefore, it should beunderstood that the exemplary embodiment presented herein will notrepresent the only embodiment for carrying out the present invention.

The following detailed description includes specific details forproviding a full understanding of the present invention. However, itwill be apparent to anyone skilled in the art that the present inventioncan be carried out without referring to the above-mentioned specificdetails. In some cases, in order to avoid any ambiguity in the conceptof the present invention, the disclosed structure and device may beomitted, or the disclosed structure and device may be illustrated as ablock diagram based on their core functions.

Although diverse mobile communication systems applying the presentinvention may exist, a wireless LAN (WLAN) system will hereinafter bedescribed in detail as an example of such mobile communication system.

1. Wireless LAN (WLAN) System 1-1. General Wireless LAN (WLAN) System

FIG. 1 is a diagram showing an exemplary configuration of a wireless LAN(WLAN) system.

As shown in FIG. 1, a wireless LAN (WLAN) includes one or more BasicService Set (BSS). A BSS is a set (or group) of stations (STAs) thatsuccessfully achieve synchronization so as to communication with oneanother.

As a logical entity including a Medium Access Control (MAC) and aPhysical Layer interface for a wireless medium, an STA includes anaccess point (AP) and a non-AP Station. Among the STAs, a portabledevice (or terminal) that is operated by a user corresponds to a non-APStation. And, therefore, when an entity is simply mentioned to as anSTA, the STA may also refer to a non-AP Station. Herein, the non-APStation may also be referred to as other terms, such as a terminal, awireless transmit/receive unit (WTRU), a user equipment (UE), a mobilestation (MS), a mobile terminal, a mobile subscriber unit, and so on.

Additionally, the AP is an entity providing its associated station (STA)with an access to a distribution system (DS) through a wireless medium.Herein, the AP may also be referred to as a centralized controller, abase station (B), a Node-B, a base transceiver system (BTS), a personalbasic service set central point/access point (PCP/AP), a sitecontroller, and so on.

A BSS may be categorized as an infrastructure BSS and an independent BSS(IBSS).

The BSS shown in FIG. 1 corresponds to an IBSS. The IBSS refers to a BSSthat does not include an AP. And, since the BSS does not include an AP,access to the DS is not authorized (or approved), and, therefore, theIBSS functions as a self-contained network.

FIG. 2 is a diagram showing another exemplary configuration of awireless LAN (WLAN) system.

The BSS shown in FIG. 2 corresponds to an infrastructure BSS. Theinfrastructure BSS includes one or more STAs and APs. As a rule,although the communication between non-AP STAs is established by passingthrough the AP, in case a direct link is configured between the non-APSTAs, direct communication may also be established between the non-APSTAs.

As shown in FIG. 2, a plurality of infrastructure BSSs may beinterconnected to one another through the DS. The plurality of BSSsbeing interconnected to one another through the DS is collectivelyreferred to as an extended service set (ESS). The STAs being included inthe ESS may perform communication between one another, and, a non-AP STAmay shift (or relocate) from one BSS to another BSS within the same ESSwhile performing uninterrupted communication.

As a mechanism that connects the plurality of APs, the DS is notnecessarily required to correspond to a network. As long as the DS iscapable of providing a predetermined distribution service, there is nolimitation in the structure or configuration of the DS. For example, theDS may correspond to a wireless network, such as a mesh network, or theDS may correspond to a physical structure (or entity) that connects theAPs to one another.

Hereinafter, a channel bonding method that is performed in a wirelessLAN system will hereinafter be described in detail based on thedescription presented above.

1-2. Channel Bonding in a Wireless LAN (WLAN) System

FIG. 3 is a diagram describing a channel in a 60 GHz band for describinga channel bonding operation according to an exemplary embodiment of thepresent invention.

As shown in FIG. 3, 4 channels may be configured in a 60 GHz band, and ageneral channel bandwidth may be equal to 2.16 GHz. An ISM band (57GHz˜66 GHz), which is available for usage in 60 GHz, may be differentlyregulated in accordance with the circumstances (or situations) of eachcountry. Generally, among the channels shown in FIG. 3, since Channel 2is available for usage is all regions, Channel 2 may be used as adefault channel. Channel 2 and Channel 3 may be used is most regionsexcluding Australia. And, accordingly, Channel 2 and Channel 3 may beused for channel bonding. However, it shall be understood that diversechannels may be used for channel bonding. And, therefore, the presentinvention will not be limited to only one or more specific channels.

FIG. 4 is a diagram describing a basic method for performing channelbonding in a wireless LAN (WLAN) system.

The example shown in FIG. 4 corresponds to an example of combining two20 MHz channels and operating (or using) the combined channels for 40MHz channel bonding in an IEEE 802.11n system. In case of an IEEE802.11ac system, 40/80/160 MHz channel bonding may be performed.

The two exemplary channels of FIG. 4 include a primary channel and asecondary channel, and the STA may examine the channel status of theprimary channel, among the two channels, by using a CSMA/CA method. Ifthe primary channel is idle during a constant backoff interval, and, ata time point where the backoff count is equal to 0, if the secondarychannel is idle during a predetermined period of time (e.g., PIFS), theSTA may transmit data by combining the primary channel and the secondarychannel.

However, in case of performing contention-based channel bonding, asshown in FIG. 4, as described above, since channel bonding can beperformed only in a restricted case where the secondary channelmaintains the idle state during a predetermined period of time at a timepoint where the backoff count for the primary channel is expired, theusage of channel bonding is very restricted (or limited). And,therefore, there lies a difficulty in that measures cannot be flexiblytaken in accordance with the circumstances (or situation) of the medium.

Accordingly, in an aspect of the present invention, a solution (ormethod) for performing scheduling-based access by having the AP transmitscheduling information to the STAs is proposed. Meanwhile, in anotheraspect of the present invention, a solution (or method) for performingcontention-based channel access based on the above-described schedulingor independently from the above-described scheduling is proposed.Furthermore, in yet another aspect of the present invention, a methodfor performing communication through a spatial sharing technique basedon beamforming is proposed.

1-3. Beacon Interval Configuration

FIG. 5 is a diagram describing a configuration of a beacon interval.

In an 11ad-based DMG BSS system, the time of medium may be divided intobeacon intervals. A lower level period within the beacon interval may bereferred to as an access period. Each of the different access periodswithin one beacon interval may have a different access rule. Suchinformation on the access period may be transmitted by an AP or personalbasic service set control point (PCP) to a non-AP STA or non-PCP.

As shown in the example of FIG. 5, one beacon interval may include oneBeacon Header Interval (BHI) and one Data Transfer Interval (DTI). Asshown in FIG. 4, the BHI may include a Beacon Transmission Interval(BTI), an Association Beamforming Training (A-BFT), and an AnnouncementTransmission Interval (ATI).

The BTI refers to a period (or section or duration) during which onemore DMG beacon frames may be transmitted. The A-BFT refers to a periodduring which beamforming training is performed by an STA, which hastransmitted a DMG beacon frame during a preceding BTI. The ATI refers toa request-response based management access period between PCP/AP andnon-PCP/non-AP STA.

Meanwhile, the Data Transfer Interval (DTI) refers to a period duringwhich a frame exchange is performed between the STAs. And, as shown FIG.5, one or more Contention Based Access Periods (CBAPs) and one or moreService Periods (SPs) may be allocated (or assigned) to the DTI.Although FIG. 5 shows an example where 2 CBAPs and 2 SPs are allocatedto the DCI, this is merely exemplary. And, therefore, the presentinvention is not necessarily required to be limited only to this.

Hereinafter, a physical layer configuration in a wireless LAN (WLAN)system, in which the present invention is to be applied, will bedescribed in detail.

1-4. Physical Layer Configuration

It will be assumed that the wireless LAN (WLAN) system according to anexemplary embodiment of the present invention may provide 3 differentmodulations mode as shown below.

TABLE 1 PHY MCS Note Control PHY 0 Single carrier PHY  1 . . . 12 (lowpower SC PHY) (SC PHY) 25 . . . 31 OFDM PHY 13 . . . 24

Such modulation modes may be used for satisfying different requirements(e.g., high throughput or stability). Depending upon the system, amongthe modulation modes presented above, only some of the modulation modesmay be supported.

FIG. 6 is a diagram describing a physical configuration of a legacyradio frame.

It will be assumed that all Directional Multi-Gigabit (DMG) physicallayers commonly include the fields that are shown below in FIG. 6.However, a regulation method of each individual field and amodulation/coding scheme used in each field may vary depending upon eachmode.

As shown in FIG. 6, a preamble of a radio frame may include a ShortTraining Field (STF) and a Channel Estimation (CE). Additionally, theradio frame may also include a header and a data field as a payload ofthe radio frame and may optionally include a training (TRN) field forbeamforming.

FIG. 7 and FIG. 8 are diagrams describing a configuration of a headerfield of the radio frame shown in FIG. 6.

More specifically, FIG. 7 illustrates a case where a Single Carrier (SC)mode is used. In the SC mode, the header may include informationindicating an initial value of scrambling, information indicating aModulation and Coding Scheme (MCS) and a data length, informationindicating the presence or absence of an additional Physical ProtocolData Unit (PPDU), and information on a packet type, a training length,aggregation or non-aggregation, a presence or absence of a beam trainingrequest, a last Received Signal Strength Indicator (RSSI), truncation ornon-truncation, a Header Check Sequence (HCS), and so on. Additionally,as shown in FIG. 7, the header has 4 bits of reserved bits, and, in thedescription presented below, such reserved bits may also be used.

Additionally, FIG. 8 illustrates a detailed configuration of a headercorresponding to a case where the OFDM mode is applied. the header mayinclude information indicating an initial value of scrambling,information indicating a MCS and a data length, information indicatingthe presence or absence of an additional PPDU, and information on apacket type, a training length, aggregation or non-aggregation, apresence or absence of a beam training request, a last RSSI, truncationor non-truncation, a Header Check Sequence (HCS), and so on.Additionally, as shown in FIG. 8, the header has 2 bits of reservedbits, and, just as in the case of FIG. 7, in the description presentedbelow, such reserved bits may also be used.

As described above, the IEEE 802.11ay system considers for the firsttime the adoption of channel bonding the MIMO technique to the legacy11ad system. In order to implement channel boning and MIMO, the 11aysystem requires a new PPDU structure. In other words, when using thelegacy 11ad PPDU structure, there are limitations in supporting thelegacy user equipment (UE) and implementing channel bonding and MIMO atthe same time.

For this, a new field for the 11ay UE may be defined after the legacypreamble and legacy header field for supporting the legacy UE. And,herein, channel bonding and MIMO may be supported by using the newlydefined field.

FIG. 9 is a diagram showing a PPDU structure according to a preferredembodiment of the present invention. In FIG. 9, a horizontal axis maycorrespond to a time domain, and a vertical axis may correspond to afrequency domain.

When two or more channels are bonded, a frequency band having apredetermined size (e.g., a 400 MHz band) may exist between a frequencyband (e.g., 1.83 GHz) that is used between each channel. In case of aMixed mode, a legacy preamble (legacy STF, legacy CE) is duplicatedthrough each channel. And, according to the exemplary embodiment of thepresent invention, it may be considered to perform the transmission (gapfilling) of a new STF and CE field along with the legacy preamble at thesame time through the 400 MHz band between each channel.

In this case, as shown in FIG. 9, the PPDU structure according to thepresent invention has a structure of transmitting ay STF, ay CE, ayHeader B, and ay payload after legacy preamble, legacy header, and ayHeader A via wideband. Therefore, the ay Header and ay Payload fields,which are transmitted after the Header field, may be transmitted throughthe channels that are used for the channel bonding. Hereinafter, inorder to differentiate the ay Header from the legacy Header, the ayHeader may be referred to as an enhanced directional multi-gigabit(EDMG) Header, and the corresponding terms may be used interchangeably.

For example, a total of 6 channels or 8 channels (each corresponding to2.16 GHz) may exist in the 11ay system, and a maximum of 4 channels maybe bonded and transmitted to a single STA. Accordingly, the ay headerand the ay Payload may be transmitted through bandwidths of 2.16 GHz,4.32 GHz, 6.48 GHz, and 8.64 GHz.

Alternatively, a PPDU format of a case where the legacy preamble isrepeatedly transmitted without performing the above-describedgap-filling may also be considered.

In this case, since the Gap-Filling is not performed, the PPDU has aformat of transmitting the ay STF, ay CE, and ay Header B after thelegacy preamble, legacy header, and ay Header A without the GF-STF andGF-CE fields, which are illustrated in dotted lines in FIG. 8.

FIG. 10 is a diagram showing a simple PPDU structure that can be appliedto the present invention. When briefly summarizing the above-describedPPDU format, the PPDU format may be illustrated as shown in FIG. 10.

As shown in FIG. 10, the PPDU format that is applicable to the 11aysystem may include L-STF, L-CEF, L-Header, EDMG-Header-A, EDMG-STF,EDMG-CEF, EDMG-Header-B, Data, and TRN fields, and the above-mentionedfields may be selectively included in accordance with the format of thePPDU (e.g., SU PPDU, MU PPDU, and so on).

Herein, the part (or portion) including the L-STF, L-CEF, and L-headerfields may be referred to as a Non-EDMG portion, and the remaining part(or portion) may be referred to as an EDMG portion (or region).Additionally, the L-STF, L-CEF, L-Header, and EDMG-Header-A fields maybe referred to as pre-EDMG modulated fields, and the remaining fieldsmay be referred to as EDMG modulated fields.

The preamble is a part of the PPDU that is used for packet detection,AGC, frequency offset estimation, synchronization, indication ofmodulation (SC or OFDM) and channel estimation. The format of thepreamble is common to both OFDM packets and SC packets. The preamble isconfigured of two parts: the Short Training field and the ChannelEstimation field).

3. Embodiment which May be Applied to the Present Invention

In what follows, a method for composing a TRN subfield in the OFDM modebased on the aforementioned composition (namely a TRN subfield for EDMGOFDM PPDU) and a method for transmitting and receiving signals includingthe TRN subfield based the composition method will be described indetail.

Now, a TRN subfield structure in the OFDM mode which may be applied tothe present invention will be first described in detail.

3.1 TRN Subfield in the OFDM Mode 3.1.1. Sequence of OFDM TRN Subfield

According to the present invention, the TRN subfield for EDMG OFDM PPDUmay be configured by using/based on the EDMG CEF in the OFDM mode orEDMG STF in the OFDM mode. Similarly, by taking into account Peak toAverage Power Ratio (PAPR) performance, the TRN subfield for EMDG OFDMPPDU may be configured by using/based on a sequence with good PAPRperformance.

First, the EDMG CEF field which may be applied to the present inventionwill be described in detail as follows.

The structure of the EDMG-CEF field depends on the number of contiguous2.16 GHz channels over which an EDMG PPDU is transmitted and the number,i_(STS), of space-time streams.

First, Seq_(left,N) ^(iSTS) and Seq_(right,N) ^(iSTS) sequences oflength N used for definition of the EDMG-CEF field are defined as shownin FIGS. 11 to 30 depending on the value of N. Here, N may have one ofthe values 176, 385, 595, and 804.

FIG. 11 illustrates Seq_(left,176) ^(iSTS) per space-time stream, andFIG. 12 illustrates Seq_(right,176) ^(iSTS) per space-time stream.

FIGS. 13 and 14 illustrate Seq_(left,385) ^(iSTS) per space-time stream;and FIGS. 15 and 16 illustrate Seq_(right,385) ^(iSTS) per space-timestream.

FIGS. 17 to 19 illustrate Seq_(left,595) ^(iSTS) per space-time stream;and FIGS. 20 to 22 illustrate Seq_(right,595) ^(iSTS) per space-timestream.

FIGS. 23 to 26 illustrate Seq_(left,804) ^(iSTS) per space-time stream;and FIGS. 27 to 30 illustrate Seq_(right,804) ^(iSTS) per space-timestream.

At this time, for transmission of an EDMG PPDU in the EDMG OFDM modeover a 2.16 GHz channel, the EDMG-CEF sequence in the frequency domainfor the i-th space-time stream may be defined by the mathematicalequation below. At this time, Seq_(left,176) ^(iSTS) and Seq_(right,176)^(iSTS) may be defined as shown in FIGS. 11 and 12.EDMG-CEF^(i) ^(STS) _(−177,177)=[Seq^(i) ^(STS)_(left,176),0,0,0,Seq^(i) ^(STS) _(right,176)], for i_(STS)=1,2,3,4,5,6,7,8  [Equation 1]

For transmission of an EDMG PPDU in the EDMG OFDM mode over a 4.32 GHzchannel, the EDMG-CEF sequence in the frequency domain for the i-thspace-time sequence may be defined by the mathematical equation below.At this time, Seq_(left,385) ^(iSTS) and Seq_(right,385) ^(iSTS) may bedefined as shown in FIGS. 13 to 16.EDMG-CEF^(i) ^(STS) _(−386,386)=[Seq^(i) ^(STS)_(left,385),0,0,0,Seq^(i) ^(STS) _(right,385)], for i_(STS)=1,2,3,4,5,6,7,8  [Equation 2]

For transmission of an EDMG PPDU in the EDMG OFDM mode over a 6.48 GHzchannel, the EDMG-CEF sequence in the frequency domain for the i-thspace-time sequence may be defined by the mathematical equation below.At this time, Seq_(left,595) ^(iSTS) and Seq_(right,595) ^(iSTS) may bedefined as shown in FIGS. 17 to 22.EDMG-CEF^(i) ^(STS) _(−596,596)=[Seq^(i) ^(STS)_(left,595),0,0,0,Seq^(i) ^(STS) _(right,595)], for i_(STS)=1,2,3,4,5,6,7,8  [Equation 3]

For transmission of an EDMG PPDU in the EDMG OFDM mode over an 8.64 GHzchannel, the EDMG-CEF sequence in the frequency domain for the i-thspace-time sequence may be defined by the mathematical equation below.At this time, Seq_(left,804) ^(iSTS) and Seq_(right,804) ^(iSTS) may bedefined as shown in FIGS. 23 to 30.EDMG-CEF^(i) ^(STS) _(−805,805)=[Seq^(i) ^(STS)_(left,804),0,0,0,Seq^(i) ^(STS) _(right,804)], for i_(STS)=1,2,3,4,5,6,7,8  [Equation 4]

When the OFDM sampling rate F_(S) is N_(CB)×2.64 GHz, and sample timeT_(S)=1/F_(S), transmit waveform of the EDMG-CEF field in the timedomain may be defined by the mathematical equation given below. HereN_(CB) represents the number of contiguous or bonded (or combined)channels.

$\begin{matrix}{\mspace{79mu}{{{r_{{EDMG} - {CEF}}^{n,i_{TX}}\left( {qT}_{s} \right)} = {{\frac{1}{\sqrt{N_{STS} \cdot N_{{EDMG} - {CEF}}^{Tone}}}{{w\left( {qT}_{s} \right)} \cdot \cdot {\sum\limits_{k = {- N_{SR}}}^{N_{SR}}{\sum\limits_{i_{STS} = 1}^{N_{STS}}{{\left\lbrack Q_{k} \right\rbrack_{i_{TX},i_{STS}}\left\lbrack P_{{EDMG} - {CEF}} \right\rbrack}_{i_{STS},n}{EDMG}}}}}} - {{CEF}_{k}^{i_{STS}}{\exp\left( {j\; 2\;\pi\; k\;{\Delta_{F}\left( {{qT}_{s} - T_{{GI}\mspace{11mu}{long}}} \right)}} \right)}}}},{1 \leq n \leq N_{{EDMG} - {CEF}}^{N_{STS}}}}} & \left\lbrack {{Equation}\mspace{14mu} 5} \right\rbrack\end{matrix}$

Each parameter in the equation above may be defined as follows.N _(EDMG-CEF) ^(Tone) =N _(ST) −N _(DC)  [Equation 6]is the total number of active tones

-   Q_(k) is the spatial mapping matrix per k^(th) subcarrier-   P_(EDMG-CEF) is the EDMG-CEF mapping matrix defined below-   N_(EDMG-CEF) ^(N) ^(STS) is the number of OFDM symbols in the    EDMG-CEF for a given total number of space-time streams N_(STS)    defined below-   [ ]_(m,n) is a matrix element from m^(th) row and n^(th) column-   w(qT_(s)) is the window function applied to smooth the transitions    between consecutive OFDM symbols. Its definition is implementation    dependent.

In what follows, for the convenience of descriptions, a structureproposed by the present invention will be described in detail withreference to an example where a sequence of an EDMG-CEF field isutilized as a sequence of the OFDM TRN subfield. However, it should benoted that according to another embodiment of the present invention, the‘EDMG-CEF’ sequence in what follows may be replaced with anothersequence (for example, an EMDG-STF sequence or another sequenceexhibiting decent PAPR performance).

3.1.2. Symbol Length of OFDM TRN Subfield

In the conventional systems, only the TRN subfield in the SC mode ratherthan OFDM mode is defined. At this time, the TRN subfield in the SC modemay have a TRN subfield sequence having a different length depending onthe value of TRN_BL. At this time, the TRN_BL value may be configureddifferently according to the ‘TRN Subfield Sequence Length field’ valueof the EDMG Header-A field. As one example, when the TRN SubfieldSequence Length field of the EDMG-Header-A is 0, TRN_BL is set to 128;when the TRN Subfield Sequence Length field of the EDMG-Header-A is 1,TRN_BL is set to 256; and when the TRN Subfield Sequence Length field ofthe EDMG-Header-A is 2, TRN_BL is set to 64. At this time, when the TRNSubfield Sequence Length field of the EDMG-Header-A is 0, it mayindicate ‘Normal’ while, when it is 2, it may indicate ‘Short’.

Here, the TRN sequence in the SC mode may be configured of 6 Golaycomplementary sequences Ga and Gb as shown in the mathematical equationgiven below.TRN^(i) _(basic)=[Ga ^(i) _(N) ,−Gb ^(i) _(N) ,Ga ^(i) _(N) ,Gb ^(i)_(N) ,Ga ^(i) _(N) ,−Gb ^(i) _(N)]  [Equation 7]

In the equation above, i may represent a space-time stream or a transmitchain.

As described above, the length of the TRN subfield may be configureddifferently depending on the TRN Subfield Sequence Length field of theEDMG Header-A. Accordingly, duration of a TRN subfield sequence for eachcase may be determined as follows.

-   -   When TRN Subfield Sequence Length field of EDMG-Header-A is 0,        6*128*T_(C)=768*T_(C).    -   When TRN Subfield Sequence Length field of EDMG-Header-A is 1,        6*256*T_(C)=1536*T_(C).    -   When TRN Subfield Sequence Length field of EDMG-Header-A is 2,        6*64*T_(C)=384*T_(C).

Here, T_(C) denotes a chip rate of the SC mode and may be 0.57 ns.

If duration of the TRN subfield sequence in the SC mode described aboveis expressed in terms of T_(S), OFDM sample time parameter, it may beexpressed as follows. (T_(C)=T_(S)*3/2, T_(S)=0.38 ns).

-   -   When TRN Subfield Sequence Length field of EDMG-Header-A is 0,        6*128*T_(C)=1152*T_(S)    -   When TRN Subfield Sequence Length field of EDMG-Header-A is 1,        6*256*T_(C)=2304*T_(S)    -   When TRN Subfield Sequence Length field of EDMG-Header-A is 2,        6*64*T_(C)=576*T_(S)

As described above, conventional systems do not define symbol length ofthe TRN subfield in the OFDM mode. In this regard, examples which may beused as the symbol length of the TRN subfield in the OFDM mode for the11ay system to which the present invention may be applied will bedescribed in detail.

The 802.11ay system to which the present invention may be applied maysupport signal transmission and reception through a channel bonded withone to four channels. Therefore, according to the number of bondedchannels, a basic OFDM TRN subfield, an OFDM TRN subfield correspondingto one OFDM symbol, which may be applied to the present invention may beconfigured as follows.

(1) Single Channel

In this case, the sample frequency F_(S) in the OFDM mode is 2.64 GHz,and sample time T_(S) is 0.38 ns (=T_(C)*⅔).

A transmitter applies a 512-point Inverse Discrete Fourier Transform(IDFT) on the OFDM EDMG-CEF and inserts cyclic prefix to compose theOFDM TRN subfield.

At this time, the length of the inserted CP (or the number of samples)may correspond to 48, 96, 192, 32, 64, or 128 samples. In other words,the length of the inserted CP in the time domain may correspond to48*T_(S), 96*T_(S), 192*T_(S) (=72.72 ns), 32*T_(S), 64*T_(S), or128*T_(S). In this case, the total number of samples for one OFDM symbolmay be 560, 608, 704, 544, 576, or 640. Also, in this case, the lengthof each TRN subfield in the time domain may be 560*T_(S), 608*T_(S),704*T_(S), 544*T_(S), 576*T_(S), or 640*T_(S).

(2) 2 Channel Bonding

In this case, the sample frequency F_(S) in the OFDM mode is 5.28 GHz,and sample time T_(S) is 0.19 ns (=T_(C)/3).

A transmitter applies a 512-point IDFT on the OFDM EDMG-CEF and insertscyclic prefix to compose the OFDM TRN subfield.

At this time, the length of the inserted CP (or the number of samples)may correspond to 96, 192, 384, 64, 128, or 256 samples. In other words,the length of the inserted CP in the time domain may correspond to96*T_(S), 192*T_(S), 384*T_(S) (=72.72 ns), 64*T_(S), 128*T_(S), or256*T_(S). In this case, the total number of samples for one OFDM symbolmay be 1120, 1216, 1408, 1088, 1152, or 1280. Also, in this case, thelength of each TRN subfield in the time domain may be 1120*T_(S),1216*T_(S), 1408*T_(S), 1088*T_(S), 1152*T_(S), or 1280*T_(S).

(3) 3 Channel Bonding

In this case, the sample frequency F_(S) in the OFDM mode is 7.92 GHz,and sample time T_(S) is 0.13 ns (=2*T_(C)/9).

A transmitter applies a 512-point IDFT on the OFDM EDMG-CEF and insertscyclic prefix to compose the OFDM TRN subfield.

At this time, the length of the inserted CP (or the number of samples)may correspond to 144, 288, 576, 96, 192, or 384 samples. In otherwords, the length of the inserted CP in the time domain may correspondto 144*T_(S), 288*T_(S), 576*T_(S) (=72.72 ns), 96*T_(S), 192*T_(S), or384*T_(S). In this case, the total number of samples for one OFDM symbolmay be 1680, 1824, 2112, 1632, 1728, or 1920. Also, in this case, thelength of each TRN subfield in the time domain may be 1680*T_(S),1824*T_(S), 2112*T_(S), 1632*T_(S), 1728*T_(S), or 1920*T_(S).

(4) 4 Channel Bonding

In this case, the sample frequency F_(S) in the OFDM mode is 10.56 GHz,and sample time T_(S) is 0.09 ns (=T_(C)/6).

A transmitter applies a 2018-point IDFT on the OFDM EDMG-CEF and insertscyclic prefix to compose the OFDM TRN subfield.

At this time, the length of the inserted CP (or the number of samples)may correspond to 192, 384, 768, 128, 256, or 512 samples. In otherwords, the length of the inserted CP in the time domain may correspondto 192*T_(S), 384*T_(S), 768*T_(S) (=72.72 ns), 128*T_(S), 256*T_(S), or512*T_(S). In this case, the total number of samples for one OFDM symbolmay be 2240, 2432, 2816, 2176, 2304, or 2560. Also, in this case, thelength of each TRN subfield in the time domain may be 2240*T_(S),2432*T_(S), 2816*T_(S), 2176*T_(S), 2304*T_(S), or 2560*T_(S).

According to the present invention, the transmitter may compose an OFDMTRN subfield corresponding to one OFDM symbol by using/based on theCP+IDFT (OFDM EDMG-CEF) structure according to the total number of CPsamples described above.

Also, similarly to the case of SC mode, Header-A field of an EDMG OFDMPPDU may include a field (for example, TRN Subfield Sequence Lengthfield) indicating the length of a TRN field. In what follows, a methodfor composing a TRN subfield according to the value of theaforementioned field will be described in detail.

In the present invention, the TRN subfield according to the value of theaforementioned field may be configured by repeating the basic TRNsubfield (CP+IDFT (OFDM EDMG-CEF)) one to five times. Therefore, in whatfollows, similarly to the SC mode, a TRN subfield structure (forexample, symbol length of the TRN subfield) which may be appliedaccording to the ‘TRN Subfield Sequence Length field’ value of the EMDGHeader-A field will be described in detail.

1) The Case where TRN Subfield Sequence Length Field of EDMG-Header-A is0 (TRN_BL is 128, 1152*T_(S))

FIG. 31 illustrates a TRN subfield structure corresponding to one OFDMsymbol.

As shown in FIG. 31, if TRN Subfield Sequence Length field of theEDMG-Header-A is 0, the corresponding TRN subfield structure may beconfigured of a TRN subfield structure corresponding to one OFDM symbol(namely a structure configured of one basic OFDM TRN subfield).

FIGS. 32 and 33 illustrate a TRN subfield structure corresponding twoOFDM symbols.

As shown in FIGS. 32 and 33, if TRN Subfield Sequence Length field ofthe EDMG-Header-A is 0, the corresponding TRN subfield structure may beconfigured of a TRN subfield structure corresponding to two OFDM symbols(namely a structure configured of two basic OFDM TRN subfields).

At this time, CP may be used twice as shown in FIG. 32, or only one CPmay be used over two OFDM symbols as shown in FIG. 33.

FIG. 34 illustrates a TRN subfield structure corresponding to three OFDMsymbols.

As shown in FIG. 34, if TRN Subfield Sequence Length field of theEDMG-Header-A is 0, the corresponding TRN subfield structure may beconfigured of a TRN subfield structure corresponding to three OFDMsymbols (namely a structure configured of three basic OFDM TRNsubfields).

FIGS. 35 and 36 illustrate a TRN subfield structure corresponding tofour OFDM symbols.

As shown in FIG. 36, if TRN Subfield Sequence Length field of theEDMG-Header-A is 0, the corresponding TRN subfield structure may beconfigured of a TRN subfield structure corresponding to four OFDMsymbols (namely a structure configured of four basic OFDM TRNsubfields).

At this time, CP may be used four times for each symbol as shown in FIG.35, or only two CPs may be used over four OFDM symbols as shown in FIG.36.

2) The Case where TRN Subfield Sequence Length Field of EDMG-Header-A is1 (TRN_BL is 256, 2304*T_(S))

If TRN Subfield Sequence Length field of the EDMG-Header-A is 1, asshown in FIGS. 31 to 36, the corresponding TRN subfield may beconfigured of a TRN subfield structure corresponding to one OFDM symbol(namely a structure configured of one basic OFDM TRN subfield), a TRNsubfield structure corresponding to two OFDM symbols (namely a structureconfigured of two basic OFDM TRN subfields), a TRN subfield structureconfigured of three OFDM symbols (namely a structure configured of threebasic OFDM TRN subfields), or a TRN subfield structure corresponding tofour OFDM symbols (namely a structure configured of four basic OFDM TRNsubfields).

In addition, if TRN Subfield Sequence Length field of the EDMG-Header-Ais 1, as shown in FIG. 37 or 38, the corresponding TRN subfield may beconfigured of a TRN subfield structure corresponding to five or six OFDMsymbols.

FIG. 37 illustrates a TRN subfield structure corresponding to five OFDMsymbols.

As shown in FIG. 37, if TRN Subfield Sequence Length field of theEDMG-Header-A is 1, the corresponding TRN subfield structure may beconfigured of a TRN subfield structure corresponding to five OFDMsymbols (namely a structure configured of five basic OFDM TRNsubfields).

FIG. 38 illustrates a TRN subfield structure corresponding to six OFDMsymbols.

As shown in FIG. 38, if TRN Subfield Sequence Length field of theEDMG-Header-A is 1, the corresponding TRN subfield structure may beconfigured of a TRN subfield structure corresponding to six OFDM symbols(namely a structure configured of six basic OFDM TRN subfields).

3) The Case where TRN Subfield Sequence Length Field of EDMG-Header-A is2 (TRN_BL is 64, 576*T_(S))

If TRN Subfield Sequence Length field of the EDMG-Header-A is 2, asshown in FIGS. 31 to 33, the corresponding TRN subfield may beconfigured of a TRN subfield structure corresponding to one OFDM symbol(namely a structure configured of one basic OFDM TRN subfield) or a TRNsubfield structure corresponding to two OFDM symbols (namely a structureconfigured of two basic OFDM TRN subfields).

In a preferred embodiment to which the present invention may be applied,a TRN subfield structure according to the value of the TRN SubfieldSequence Length field of the EDMG Header-A field (namely a structurewhere the basic TRN subfield structure is repeated for a predeterminednumber of times) may be determined so as to be aligned with the TRNsubfield of the SC mode in the time domain.

In one example, in the normal case (namely when the TRN SubfieldSequence Length field of the EDMG-Header-A is 0), considering that theTRN subfield of the SC mode is aligned with the TRN subfield of the OFDMmode in the time domain, the TRN subfield of the OFDM mode correspondingto the normal case may be configured of one OFDM symbol (704*T_(S) whena long Guard Interval (GI) with a length of 72.72 ns is used) or twoOFDM symbols (1408*T_(S) when a long Guard Interval (GI) with a lengthof 72.72 ns is used).

At this time, similarly to the SC mode case, to easily compose the OFDMTRN subfield into a Normal/Short/Long structure according to the valueindicated by/included in the TRN Subfield Sequence Length field of theEDMG Header-A field, the TRN subfield structure in the normal case maybe configured of two OFDM symbols.

In other words, according to a preferred embodiment to which the presentinvention may be applied, if the TRN subfield Sequence Length field ofthe EDMG-Header-A is 0, the TRN subfield may be configured of a TRNsubfield structure corresponding to two OFDM symbols as shown in FIG.32; if the TRN subfield Sequence Length field of the EDMG-Header-A is 1,the TRN subfield may be configured of a TRN subfield structurecorresponding to four OFDM symbols as shown in FIG. 35; and if the TRNsubfield Sequence Length field of the EDMG-Header-A is 0, the TRNsubfield may be configured of a TRN subfield structure corresponding toone OFDM symbols as shown in FIG. 31.

By employing the composition described above, time duration of the TRNsubfield of the OFDM mode may be aligned with that of the TRN subfieldof the SC mode in the time domain.

As described above, in the case of single channel, 512-point IDFT may beapplied; in the case of 2 channel bonding, 1024-point IDFT; in the caseof 3 channel bonding, 1536-point IDFT; and in the case of 4 channelbonding, 2048-point IDFT. Also, the number of CP samples which may beapplied is 48, 96, 192, 32, 64, or 128 for the case of single channelbonding; 96, 192, 384, 64, 128, or 256 for the case of 2 channelbonding; 144, 288, 576, 96, 192, or 384 for the case of 3 channelbonding; and 192, 384, 768, 128, 256, or 512 for the case of 4 channelbonding.

In the present invention, to compose a TRN subfield which is based onrepetition of a TRN subfield structure corresponding to one OFDM symbol,the order of CP and IDFT (OFDM EDMG-CEF) may be changed in various ways.

3.1.3. OFDM TRN Field Structure for Multi-Streams

The 11ay system applicable for the present invention may support up to 8space-time streams to support the Multiple Input Multiple Output scheme.In what follows, an OFDM TRN subfield structure according to the totalnumber of supported streams will be described in detail.

For the convenience of descriptions, in what follows, a signal obtainedby repeating the TRN subfield structure, which corresponds to one OFDMsymbol obtained through insertion of CP after IDFT is applied to theOFDM EDMG-CEF of the i-th space-time stream, one, two, or four timesaccording to the value of the TRN Subfield Sequence Length field of theEDMG-Header-A is denoted as OFDM_TRN_basic_i.

Accordingly, the OFDM TRN subfield according to the total number ofspace time streams may be defined as follows.

Nsts=1(total number of stream: 1)

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1]

or

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −OFDM_TRN_basic_1]

(2) Nsts=2(total number of stream: 2)

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1]

OFDM_TRN_subfield_2=[OFDM_TRN_basic_2]

or

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −OFDM_TRN_basic_1]

OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, OFDM_TRN_basic_2]

(3) Nsts=3(total number of stream: 3) (w₃=exp(−j*2*pi/3))

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, OFDM_TRN_basic_1]

OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, OFDM_TRN_basic_2]

OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, −OFDM_TRN_basic_3]

or

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −OFDM_TRN_basic_1,OFDM_TRN_basic_1]

OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, −w₃ ¹*OFDM_TRN_basic_2, w₃²*OFDM_TRN_basic_2]

OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, −w₃ ³*OFDM_TRN_basic_3, w₃⁴*OFDM_TRN_basic_3]

or

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −OFDM_TRN_basic_1,OFDM_TRN_basic_1, OFDM_TRN_basic_1]

OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, OFDM_TRN_basic_2,−OFDM_TRN_basic_2, OFDM_TRN_basic_2]

OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, OFDM_TRN_basic_3,OFDM_TRN_basic_3, −OFDM_TRN_basic_3]

(4) Nsts=4(total number of stream: 4) (w₄=exp(−j*2*pi/4))

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, OFDM_TRN_basic_1]

OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, OFDM_TRN_basic_2]

OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, −OFDM_TRN_basic_3]

OFDM_TRN_subfield_4=[OFDM_TRN_basic_4, −OFDM_TRN_basic_4]

or

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −OFDM_TRN_basic_1,OFDM_TRN_basic_1, OFDM_TRN_basic_1]

OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, −w₄ ¹*OFDM_TRN_basic_2, w₄²*OFDM_TRN_basic_2, w₄ ³*OFDM_TRN_basic_2]

OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, −w₄ ⁴*OFDM_TRN_basic_3, w₄⁵*OFDM_TRN_basic_3, w₄ ⁶*OFDM_TRN_basic_3]

OFDM_TRN_subfield_4=[OFDM_TRN_basic_4, −w₄ ⁷*OFDM_TRN_basic_4, w₄⁸*OFDM_TRN_basic_4, w₄ ⁹*OFDM_TRN_basic_4]

or

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −OFDM_TRN_basic_1,OFDM_TRN_basic_1, OFDM_TRN_basic_1]

OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, OFDM_TRN_basic_2,−OFDM_TRN_basic_2, OFDM_TRN_basic_2]

OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, OFDM_TRN_basic_3,OFDM_TRN_basic_3, −OFDM_TRN_basic_3]

OFDM_TRN_subfield_4=[−OFDM_TRN_basic_4, OFDM_TRN_basic_4,OFDM_TRN_basic_4, OFDM_TRN_basic_4]

(5) Nsts=5(total number of stream: 5) (w₅=exp(−j*2*pi/5),w₆=exp(−j*2*pi/6))

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, OFDM_TRN_basic_1,OFDM_TRN_basic_1, OFDM_TRN_basic_1]

OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, OFDM_TRN_basic_2,OFDM_TRN_basic_2, OFDM_TRN_basic_2]

OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, −OFDM_TRN_basic_3,OFDM_TRN_basic_3, −OFDM_TRN_basic_3]

OFDM_TRN_subfield_4=[OFDM_TRN_basic_4, −OFDM_TRN_basic_4,OFDM_TRN_basic_4, −OFDM_TRN_basic_4]

OFDM_TRN_subfield_5=[OFDM_TRN_basic_5, OFDM_TRN_basic_5,−OFDM_TRN_basic_5, −OFDM_TRN_basic_5]

or

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −OFDM_TRN_basic_1,OFDM_TRN_basic_1, OFDM_TRN_basic_1, OFDM_TRN_basic_1, −OFDM_TRN_basic_1]

OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, −w₆ ¹*OFDM_TRN_basic_2, w₆²*OFDM_TRN_basic_2, w₆ ³*OFDM_TRN_basic_2, w₆ ⁴*OFDM_TRN_basic_2, −w₆⁵*OFDM_TRN_basic_2]

OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, −w₆ ²*OFDM_TRN_basic_3, w₆⁴*OFDM_TRN_basic_3, w₆ ⁶*OFDM_TRN_basic_3, w₆ ⁸*OFDM_TRN_basic_3 −w₆¹⁰*OFDM_TRN_basic_3]

OFDM_TRN_subfield_4=[OFDM_TRN_basic_4, −w₆ ³*OFDM_TRN_basic_4, w₆⁶*OFDM_TRN_basic_4, w₆ ⁹*OFDM_TRN_basic_4, w₆ ¹²*OFDM_TRN_basic_4 −w₆¹⁵*OFDM_TRN_basic_4]

OFDM_TRN_subfield_5=[OFDM_TRN_basic_5, −w₆ ⁴*OFDM_TRN_basic_5, w₆⁸*OFDM_TRN_basic_5, w₆ ¹²*OFDM_TRN_basic_5, w₆ ¹⁶*OFDM_TRN_basic_5 −w₆²⁰*OFDM_TRN_basic_5]

or

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −OFDM_TRN_basic_1,OFDM_TRN_basic_1, OFDM_TRN_basic_1, OFDM_TRN_basic_1, −OFDM_TRN_basic_1,OFDM_TRN_basic_1, OFDM_TRN_basic_1]

OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, OFDM_TRN_basic_2,−OFDM_TRN_basic_2, OFDM_TRN_basic_2, OFDM_TRN_basic_2, OFDM_TRN_basic_2,−OFDM_TRN_basic_2, OFDM_TRN_basic_2]

OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, OFDM_TRN_basic_3,OFDM_TRN_basic_3, −OFDM_TRN_basic_3, OFDM_TRN_basic_3, OFDM_TRN_basic_3,OFDM_TRN_basic_3, −OFDM_TRN_basic_3]

OFDM_TRN_subfield_4=[−OFDM_TRN_basic_4, OFDM_TRN_basic_4,OFDM_TRN_basic_4, OFDM_TRN_basic_4, −OFDM_TRN_basic_4, OFDM_TRN_basic_4,OFDM_TRN_basic_4, OFDM_TRN_basic_4]

OFDM_TRN_subfield_5=[OFDM_TRN_basic_5, −OFDM_TRN_basic_5,OFDM_TRN_basic_5, OFDM_TRN_basic_5, −OFDM_TRN_basic_5, OFDM_TRN_basic_5,−OFDM_TRN_basic_5, −OFDM_TRN_basic_5]

or

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −OFDM_TRN_basic_1,OFDM_TRN_basic_1, OFDM_TRN_basic_1, OFDM_TRN_basic_1]

OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, −w₅ ¹*OFDM_TRN_basic_2, w₅²*OFDM_TRN_basic_2, w₅ ³*OFDM_TRN_basic_2, w₅ ⁴*OFDM_TRN_basic_2]

OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, −w₅ ⁵*OFDM_TRN_basic_3, w₅⁶*OFDM_TRN_basic_3, w₅ ⁷*OFDM_TRN_basic_3, w₅ ⁸*OFDM_TRN_basic_3]

OFDM_TRN_subfield_4=[OFDM_TRN_basic_4, −w₅ ⁹*OFDM_TRN_basic_4, w₅¹⁰*OFDM_TRN_basic_4, w₅ ¹¹*OFDM_TRN_basic_4, w₅ ¹²*OFDM_TRN_basic_4]

OFDM_TRN_subfield_5=[OFDM_TRN_basic_5, −w₅ ¹³*OFDM_TRN_basic_5, w₅¹⁴*OFDM_TRN_basic_5, w₅ ¹⁵*OFDM_TRN_basic_5, w₅ ¹⁶*OFDM_TRN_basic_5]

(6) Nsts=6(total number of stream: 6) (w₆=exp(−j 2*pi/6))

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, OFDM_TRN_basic_1,OFDM_TRN_basic_1, OFDM_TRN_basic_1]

OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, OFDM_TRN_basic_2,OFDM_TRN_basic_2, OFDM_TRN_basic_2]

OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, −OFDM_TRN_basic_3,OFDM_TRN_basic_3, −OFDM_TRN_basic_3]

OFDM_TRN_subfield_4=[OFDM_TRN_basic_4, −OFDM_TRN_basic_4,OFDM_TRN_basic_4, −OFDM_TRN_basic_4]

OFDM_TRN_subfield_5=[OFDM_TRN_basic_5, OFDM_TRN_basic_5,−OFDM_TRN_basic_5, −OFDM_TRN_basic_5]

OFDM_TRN_subfield_6=[OFDM_TRN_basic_6, OFDM_TRN_basic_6,−OFDM_TRN_basic_6, −OFDM_TRN_basic_6]

or

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −OFDM_TRN_basic_1,OFDM_TRN_basic_1, OFDM_TRN_basic_1, OFDM_TRN_basic_1, OFDM_TRN_basic_1]

OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, −w₆ ¹*OFDM_TRN_basic_2, w₆²*OFDM_TRN_basic_2, w₆ ³*OFDM_TRN_basic_2, w₆ ⁴*OFDM_TRN_basic_2, −w₆⁵*OFDM_TRN_basic_2]

OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, −w₆ ²*OFDM_TRN_basic_3, w₆⁴*OFDM_TRN_basic_3, w₆ ⁶*OFDM_TRN_basic_3, w₆ ⁸*OFDM_TRN_basic_3 −w₆¹⁰*OFDM_TRN_basic_3]

OFDM_TRN_subfield_4=[OFDM_TRN_basic_4, −w₆ ³*OFDM_TRN_basic_4, w₆⁶*OFDM_TRN_basic_4, w₆ ⁹*OFDM_TRN_basic_4, w₆ ¹²*OFDM_TRN_basic_4 −w₆¹⁵*OFDM_TRN_basic_4]

OFDM_TRN_subfield_5=[OFDM_TRN_basic_5, −w₆ ⁴*OFDM_TRN_basic_5, w₆⁸*OFDM_TRN_basic_5, w₆ ¹²*OFDM_TRN_basic_5, w₆ ¹⁶*OFDM_TRN_basic_5 −w₆²⁰*OFDM_TRN_basic_5]

OFDM_TRN_subfield_6=[OFDM_TRN_basic_6, −w₆ ⁵*OFDM_TRN_basic_6, w₆¹⁰*OFDM_TRN_basic_6, w₆ ¹⁵*OFDM_TRN_basic_6, w₆ ²⁰*OFDM_TRN_basic_6 −w₆²⁵*OFDM_TRN_basic_6]

or

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −OFDM_TRN_basic_1,OFDM_TRN_basic_1, OFDM_TRN_basic_1, OFDM_TRN_basic_1, −OFDM_TRN_basic_1,OFDM_TRN_basic_1, OFDM_TRN_basic_1]

OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, OFDM_TRN_basic_2,−OFDM_TRN_basic_2, OFDM_TRN_basic_2, OFDM_TRN_basic_2, OFDM_TRN_basic_2,−OFDM_TRN_basic_2, OFDM_TRN_basic_2]

OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, OFDM_TRN_basic_3,OFDM_TRN_basic_3, −OFDM_TRN_basic_3, OFDM_TRN_basic_3, OFDM_TRN_basic_3,OFDM_TRN_basic_3, −OFDM_TRN_basic_3]

OFDM_TRN_subfield_4=[−OFDM_TRN_basic_4, OFDM_TRN_basic_4,OFDM_TRN_basic_4, OFDM_TRN_basic_4, −OFDM_TRN_basic_4, OFDM_TRN_basic_4,OFDM_TRN_basic_4, OFDM_TRN_basic_4]

OFDM_TRN_subfield_5=[OFDM_TRN_basic_5, −OFDM_TRN_basic_5,OFDM_TRN_basic_5, OFDM_TRN_basic_5, −OFDM_TRN_basic_5, OFDM_TRN_basic_5,−OFDM_TRN_basic_5, −OFDM_TRN_basic_5]

OFDM_TRN_subfield_6=[OFDM_TRN_basic_6, OFDM_TRN_basic_6,−OFDM_TRN_basic_6, OFDM_TRN_basic_6, −OFDM_TRN_basic_6,−OFDM_TRN_basic_6, OFDM_TRN_basic_6, −OFDM_TRN_basic_6]

(7) Nsts=7(total number of stream: 7) (w₇=exp(−j 2*pi/7))

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, OFDM_TRN_basic_1,OFDM_TRN_basic_1, OFDM_TRN_basic_1]

OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, OFDM_TRN_basic_2,OFDM_TRN_basic_2, OFDM_TRN_basic_2]

OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, −OFDM_TRN_basic_3,OFDM_TRN_basic_3, −OFDM_TRN_basic_3]

OFDM_TRN_subfield_4=[OFDM_TRN_basic_4, −OFDM_TRN_basic_4,OFDM_TRN_basic_4, −OFDM_TRN_basic_4]

OFDM_TRN_subfield_5=[OFDM_TRN_basic_5, OFDM_TRN_basic_5,−OFDM_TRN_basic_5, −OFDM_TRN_basic_5]

OFDM_TRN_subfield_6=[OFDM_TRN_basic_6, OFDM_TRN_basic_6,−OFDM_TRN_basic_6, −OFDM_TRN_basic_6]

OFDM_TRN_subfield_7=[OFDM_TRN_basic_7, −OFDM_TRN_basic_7,−OFDM_TRN_basic_7, OFDM_TRN_basic_7]

or

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −OFDM_TRN_basic_1,OFDM_TRN_basic_1, OFDM_TRN_basic_1, OFDM_TRN_basic_1, −OFDM_TRN_basic_1,OFDM_TRN_basic_1 OFDM_TRN_basic_1]

OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, OFDM_TRN_basic_2,−OFDM_TRN_basic_2, OFDM_TRN_basic_2, OFDM_TRN_basic_2, OFDM_TRN_basic_2,−OFDM_TRN_basic_2, OFDM_TRN_basic_2]

OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, OFDM_TRN_basic_3,OFDM_TRN_basic_3, −OFDM_TRN_basic_3, OFDM_TRN_basic_3, OFDM_TRN_basic_3,OFDM_TRN_basic_3, −OFDM_TRN_basic_3]

OFDM_TRN_subfield_4=[−OFDM_TRN_basic_4, OFDM_TRN_basic_4,OFDM_TRN_basic_4, OFDM_TRN_basic_4, −OFDM_TRN_basic_4, OFDM_TRN_basic_4,OFDM_TRN_basic_4, OFDM_TRN_basic_4]

OFDM_TRN_subfield_5=[OFDM_TRN_basic_5, −OFDM_TRN_basic_5,OFDM_TRN_basic_5, OFDM_TRN_basic_5, −OFDM_TRN_basic_5, OFDM_TRN_basic_5,−OFDM_TRN_basic_5, −OFDM_TRN_basic_5]

OFDM_TRN_subfield_6=[OFDM_TRN_basic_6, OFDM_TRN_basic_6,−OFDM_TRN_basic_6, OFDM_TRN_basic_6, −OFDM_TRN_basic_6,−OFDM_TRN_basic_6, OFDM_TRN_basic_6, −OFDM_TRN_basic_6]

OFDM_TRN_subfield_7=[OFDM_TRN_basic_7, OFDM_TRN_basic_7,OFDM_TRN_basic_7, −OFDM_TRN_basic_7, −OFDM_TRN_basic_7,−OFDM_TRN_basic_7, −OFDM_TRN_basic_7, OFDM_TRN_basic_7]

or

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −w₇ ¹*OFDM_TRN_basic_1, w₇²*OFDM_TRN_basic_1, w₇ ³*OFDM_TRN_basic_1, w₇ ⁴*OFDM_TRN_basic_1, −w₇⁵*OFDM_TRN_basic_1, w₇ ⁶*OFDM_TRN_basic_1]

OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, −w₇ ⁷*OFDM_TRN_basic_2, w₇⁸*OFDM_TRN_basic_2, w₇ ⁹*OFDM_TRN_basic_2, w₇ ¹⁰*OFDM_TRN_basic_2, −w₇¹¹*OFDM_TRN_basic_2, w₇ ¹²*OFDM_TRN_basic_2]

OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, −w₇ ¹³*OFDM_TRN_basic_3, w₇¹⁴*OFDM_TRN_basic_3, w₇ ¹⁵*OFDM_TRN_basic_3, w₇ ¹⁶*OFDM_TRN_basic_3, −w₇¹⁷*OFDM_TRN_basic_3, w₇ ¹⁸*OFDM_TRN_basic_3]

OFDM_TRN_subfield_4=[OFDM_TRN_basic_4, −w₇ ¹⁹*OFDM_TRN_basic_4, w₇²⁰*OFDM_TRN_basic_4, w₇ ²¹*OFDM_TRN_basic_4, w₇ ²²*OFDM_TRN_basic_4, −w₇²³*OFDM_TRN_basic_4, w₇ ²⁴*OFDM_TRN_basic_4]

OFDM_TRN_subfield_5=[OFDM_TRN_basic_5, −w₇ ²⁵*OFDM_TRN_basic_5, w₇²⁶*OFDM_TRN_basic_5, w₇ ²⁷*OFDM_TRN_basic_5, w₇ ²⁸*OFDM_TRN_basic_5, −w₇²⁹*OFDM_TRN_basic_5, w₇ ³⁰*OFDM_TRN_basic_5]

OFDM_TRN_subfield_6=[OFDM_TRN_basic_6, −w₇ ³¹*OFDM_TRN_basic_6, w₇³²*OFDM_TRN_basic_6, w₇ ³³*OFDM_TRN_basic_6, w₇ ³⁴*OFDM_TRN_basic_6, −w₇³⁵*OFDM_TRN_basic_6, w₇ ³⁶*OFDM_TRN_basic_6]

OFDM_TRN_subfield_7=[OFDM_TRN_basic_7, −w₇ ³⁷*OFDM_TRN_basic_7, w₇³⁸*OFDM_TRN_basic_7, w₇ ³⁹*OFDM_TRN_basic_7, w₇ ⁴⁰*OFDM_TRN_basic_7, −w₇⁴¹*OFDM_TRN_basic_7, w₇ ⁴²*OFDM_TRN_basic_7]

(8) Nsts=8(total number of stream: 8) (w₈=exp(−j 2*pi/8))

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, OFDM_TRN_basic_1,OFDM_TRN_basic_1, OFDM_TRN_basic_1]

OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, OFDM_TRN_basic_2,OFDM_TRN_basic_2, OFDM_TRN_basic_2]

OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, −OFDM_TRN_basic_3,OFDM_TRN_basic_3, −OFDM_TRN_basic_3]

OFDM_TRN_subfield_4=[OFDM_TRN_basic_4, −OFDM_TRN_basic_4,OFDM_TRN_basic_4, −OFDM_TRN_basic_4]

OFDM_TRN_subfield_5=[OFDM_TRN_basic_5, OFDM_TRN_basic_5,−OFDM_TRN_basic_5, −OFDM_TRN_basic_5]

OFDM_TRN_subfield_6=[OFDM_TRN_basic_6, OFDM_TRN_basic_6,−OFDM_TRN_basic_6, −OFDM_TRN_basic_6]

OFDM_TRN_subfield_7=[OFDM_TRN_basic_7, −OFDM_TRN_basic_7,−OFDM_TRN_basic_7, OFDM_TRN_basic_7]

OFDM_TRN_subfield_8=[OFDM_TRN_basic_8, −OFDM_TRN_basic_8,−OFDM_TRN_basic_8, OFDM_TRN_basic_8]

or

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −OFDM_TRN_basic_1,OFDM_TRN_basic_1, OFDM_TRN_basic_1, OFDM_TRN_basic_1, −OFDM_TRN_basic_1,OFDM_TRN_basic_1, OFDM_TRN_basic_1]

OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, OFDM_TRN_basic_2,−OFDM_TRN_basic_2, OFDM_TRN_basic_2, OFDM_TRN_basic_2, OFDM_TRN_basic_2,−OFDM_TRN_basic_2, OFDM_TRN_basic_2]

OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, OFDM_TRN_basic_3,OFDM_TRN_basic_3, −OFDM_TRN_basic_3, OFDM_TRN_basic_3, OFDM_TRN_basic_3,OFDM_TRN_basic_3, −OFDM_TRN_basic_3]

OFDM_TRN_subfield_4=[−OFDM_TRN_basic_4, OFDM_TRN_basic_4,OFDM_TRN_basic_4, OFDM_TRN_basic_4, −OFDM_TRN_basic_4, OFDM_TRN_basic_4,OFDM_TRN_basic_4, OFDM_TRN_basic_4]

OFDM_TRN_subfield_5=[OFDM_TRN_basic_5, −OFDM_TRN_basic_5,OFDM_TRN_basic_5, OFDM_TRN_basic_5, −OFDM_TRN_basic_5, OFDM_TRN_basic_5,−OFDM_TRN_basic_5, −OFDM_TRN_basic_5]

OFDM_TRN_subfield_6=[OFDM_TRN_basic_6, OFDM_TRN_basic_6,−OFDM_TRN_basic_6, OFDM_TRN_basic_6, −OFDM_TRN_basic_6,−OFDM_TRN_basic_6, OFDM_TRN_basic_6, −OFDM_TRN_basic_6]

OFDM_TRN_subfield_7=[OFDM_TRN_basic_7, OFDM_TRN_basic_7,OFDM_TRN_basic_7, −OFDM_TRN_basic_7, −OFDM_TRN_basic_7,−OFDM_TRN_basic_7, −OFDM_TRN_basic_7, OFDM_TRN_basic_7]

OFDM_TRN_subfield_8=[−OFDM_TRN_basic_8, OFDM_TRN_basic_8,OFDM_TRN_basic_8, OFDM_TRN_basic_8, OFDM_TRN_basic_8, −OFDM_TRN_basic_8,−OFDM_TRN_basic_8, −OFDM_TRN_basic_8]

or

OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −w₈ ¹*OFDM_TRN_basic_1, w₈²*OFDM_TRN_basic_1, w₈ ³*OFDM_TRN_basic_1, w₈ ⁴*OFDM_TRN_basic_1, −w₈⁵*OFDM_TRN_basic_1, w₈ ⁶*OFDM_TRN_basic_1, w₈ ⁷*OFDM_TRN_basic_1]

OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, −w₈ ⁸*OFDM_TRN_basic_2, w₈⁹*OFDM_TRN_basic_2, w₈ ¹⁰*OFDM_TRN_basic_2, w₈ ¹¹*OFDM_TRN_basic_2, −w₈¹²*OFDM_TRN_basic_2, w₈ ¹³*OFDM_TRN_basic_2, w₈ ¹⁴*OFDM_TRN_basic_2]

OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, −w₈ ¹⁵*OFDM_TRN_basic_3, w₈¹⁶*OFDM_TRN_basic_3, w₈ ¹⁷*OFDM_TRN_basic_3, w₈ ¹⁸*OFDM_TRN_basic_3, −w₈¹⁹*OFDM_TRN_basic_3, w₈ ²⁰*OFDM_TRN_basic_3, w₈ ²¹*OFDM_TRN_basic_3]

OFDM_TRN_subfield_4=[OFDM_TRN_basic_4, −w₈ ²²*OFDM_TRN_basic_4, w₈²³*OFDM_TRN_basic_4, w₈ ²⁴*OFDM_TRN_basic_4, w₈ ²⁵*OFDM_TRN_basic_4, −w₈²⁶*OFDM_TRN_basic_4, w₈ ²⁷*OFDM_TRN_basic_4, w₈ ²⁸*OFDM_TRN_basic_4]

OFDM_TRN_subfield_5=[OFDM_TRN_basic_5, −w₈ ²⁹*OFDM_TRN_basic_5, w₈³⁰*OFDM_TRN_basic_5, w₈ ³¹*OFDM_TRN_basic_5, w₈ ³²*OFDM_TRN_basic_5, −w₈³³*OFDM_TRN_basic_5, w₈ ³⁴*OFDM_TRN_basic_5, w₈ ³⁵*OFDM_TRN_basic_5]

OFDM_TRN_subfield_6=[OFDM_TRN_basic_6, −w₈ ³⁶*OFDM_TRN_basic_6, w₈³⁷*OFDM_TRN_basic_6, w₈ ³⁸*OFDM_TRN_basic_6, w₈ ³⁹*OFDM_TRN_basic_6, −w₈⁴⁰*OFDM_TRN_basic_6, w₈ ⁴¹*OFDM_TRN_basic_6, w₈ ⁴²*OFDM_TRN_basic_6]

OFDM_TRN_subfield_7=[OFDM_TRN_basic_7, −w₈ ⁴³*OFDM_TRN_basic_7, w₈⁴⁴*OFDM_TRN_basic_7, w₈ ⁴⁵*OFDM_TRN_basic_7, w₈ ⁴⁶*OFDM_TRN_basic_7, −w₈⁴⁷*OFDM_TRN_basic_7, w₈ ⁴⁸*OFDM_TRN_basic_7, w₈ ⁴⁹*OFDM_TRN_basic_7]

OFDM_TRN_subfield_8=[OFDM_TRN_basic_8, −w₈ ⁵⁰*OFDM_TRN_basic_8, w₈⁵¹*OFDM_TRN_basic_8, w₈ ⁵²*OFDM_TRN_basic_8, w₈ ⁵³*OFDM_TRN_basic_8, −w₈⁵⁴*OFDM_TRN_basic_8, w₈ ⁵⁵*OFDM_TRN_basic_8, w₈ ⁵⁶*OFDM_TRN_basic_8]

As described above, the TRN field transmitted by the transmitter may bedetermined to have a different length according to the total number ofstreams to be transmitted and the value of the TRN Subfield SequenceLength field of the EDMG Header-A field.

3.1.4. Conclusions

According to one example to which the present invention may be applied,the TRN field (or TRN subfield) of the EDMG OFDM mode may be configuredas follows.

For transmission of an EDMG PPDU in the EDMG OFDM mode through a 2.16GHz channel, an OFDM TRN_BASIC sequence in the frequency domain for theiTX-th space-time stream may be defined by the mathematical equationgiven below. At this time, Seq^(iTX) _(left,176) and Seq^(iTX)_(right,176) may correspond to Seq^(i) ^(STS) _(left,176) and Seq^(i)^(STS) _(right,176) of FIGS. 11 and 12 above.TRN_BASIC^(iTX) _(−177,177)=[Seq^(iTX) _(left,176),0,0,0,Seq^(iTX)_(right,176)], for i _(TX)=1,2,3,4,5,6,7,8  [Equation 8]

For transmission of an EDMG PPDU in the EDMG OFDM mode through a 2.16GHz channel, an OFDM TRN_BASIC sequence in the frequency domain for theiTX-th space-time stream may be defined by the mathematical equationgiven below. At this time, Seq^(iTX) _(left,385) and Seq^(iTX)_(right,385) may correspond to Seq^(i) ^(STS) _(left,385) and Seq^(i)^(STS) _(right,385) of FIGS. 13 to 16 above.TRN_BASIC^(iTX) _(−386,386)=[Seq^(iTX) _(left,385),0,0,0,Seq^(iTX)_(right,385)], for i _(TX)=1,2,3,4,5,6,7,8  [Equation 9]

For transmission of an EDMG PPDU in the EDMG OFDM mode through a 6.48GHz channel, an OFDM TRN_BASIC sequence in the frequency domain for theiTX-th space-time stream may be defined by the mathematical equationgiven below. At this time, Seq^(iTX) _(left,595) and Seq^(iTX)_(right,595) may correspond to Seq^(i) ^(STS) _(left,595) and Seq^(i)^(STS) _(right,595) of FIGS. 17 to 22 above.TRN_BASIC^(iTX) _(−596,596)=[Seq^(iTX) _(left,595),0,0,0,Seq^(iTX)_(right,595)], for i _(TX)=1,2,3,4,5,6,7,8  [Equation 10]

For transmission of an EDMG PPDU in the EDMG OFDM mode through an 8.64GHz channel, an OFDM TRN_BASIC sequence in the frequency domain for thei_(TX)-th space-time stream may be defined by the mathematical equationgiven below. At this time, Seq^(iTX) _(left,804) and Seq^(iTX)_(right,804) may correspond to Seq^(i) ^(STS) _(left,804) and Seq^(i)^(STS) _(right,804) of FIGS. 23 to 30 above.TRN_BASIC^(iTX) _(−805,805)=[Seq^(iTX) _(left,804),0,0,0,Seq^(iTX)_(right,804)], for i _(TX)=1,2,3,4,5,6,7,8  [Equation 11]

When the OFDM sampling rate F_(S)=N_(CB)*2.64 GHz, and sampling timeT_(S)=1/F_(S), a basic OFDM TRN subfield waveform for the i_(TX)-thtransmission chain (or space-time stream) in the time domain may bedefined by the mathematical equation given below.

$\begin{matrix}{{{r_{TRN\_ BASIC}^{i_{TX}}\left( {qT}_{s} \right)} = {\sum\limits_{n = 1}^{N_{TRN}^{N_{TX}}}{r_{TRN}^{n,i_{TX}}\left( {{qT}_{s} - {\left( {n - 1} \right) \cdot \left( {T_{DFT} + T_{{GI}\mspace{11mu}{long}}} \right)}} \right)}}}\mspace{79mu}{{where}\text{:}}\mspace{79mu}{{{r_{TRN}^{n,i_{TX}}\left( {qT}_{s} \right)} = {\frac{1}{\sqrt{N_{TRN}^{Tone}}}{{w\left( {qT}_{s} \right)} \cdot \cdot {\sum\limits_{k = {- N_{SR}}}^{N_{SR}}{\left\lbrack P_{TRN} \right\rbrack_{i_{TX},n}{TRN\_ BASIC}_{k}^{i_{TX}}{\exp\left( {j\; 2\;\pi\; k\;{\Delta_{F}\left( {{qT}_{s} - T_{{GI}\mspace{11mu}{long}}} \right)}} \right)}}}}}},{1 \leq n \leq N_{TRN}^{N_{TX}}}}} & \left\lbrack {{Equation}\mspace{14mu} 12} \right\rbrack\end{matrix}$

At this time, the Normal TRN subfield, Short TRN subfield, and Long TRNsubfield according to the value of the TRN Subfield Sequence Lengthfield of the EDMG Header-A field may be defined by the mathematicalequation given below.

$\begin{matrix}{{{r_{TRN\_ NORMAL}^{i_{TX}}\left( {qT}_{s} \right)} = {\sum\limits_{n = 1}^{2}{r_{TRN\_ BASIC}^{i_{TX}}\left( {{qT}_{s} - {\left( {n - 1} \right) \cdot T_{BASIC}}} \right)}}}\mspace{79mu}{{r_{TRN\_ SHORT}^{i_{TX}}\left( {qT}_{s} \right)} = {r_{TRN\_ BASIC}^{i_{TX}}\left( {qT}_{s} \right)}}{{r_{TRN\_ LONG}^{i_{TX}}\left( {qT}_{s} \right)} = {\sum\limits_{n = 1}^{4}{r_{TRN\_ BASIC}^{i_{TX}}\left( {{qT}_{s} - {\left( {n - 1} \right) \cdot T_{BASIC}}} \right)}}}} & \left\lbrack {{Equation}\mspace{14mu} 13} \right\rbrack\end{matrix}$

In the mathematical equations above, N_(CB) represents the number ofcontiguous or bonded (or combined) channels, and other parameters may bedefined as follows.N _(TRN) ^(Tone) =N _(ST) −N _(DC)  [Equation 14]is the total number of active tones

-   P_(TRN) is the TRN mapping matrix (see below)-   N_(TRN) ^(N) ^(TX) is the number of OFDM symbols in a TRN subfield    for the given total number of transmit chains N_(TX) (see below)-   [ ]_(m,n) is a matrix element from m^(th) row and n^(th) column-   w(qT_(s)) is window function applied to smooth the transitions    between consecutive OFDM symbols; its definition is implementation    specific-   q is a time sample index-   T_(BASIC) is the duration of the basic TRN subfield

From the definition above, P_(TRN) (OFDM TRN mapping matrix) may bedefined according to the N_(TX) value by the mathematical equation givenbelow.

The OFDM TRN |mapping matrix for N_(TX)=1 is defined as follows:P _(TRN)=[+1−1], N _(TRN) ^(N) ^(TX) =2  [Equation 15]

[Equation 16]

The OFDM TRN mapping matrix for N_(TX)=2 is defined as follows:

$\begin{matrix}{{P_{TRN} = \begin{bmatrix}{+ 1} & {- 1} \\{+ 1} & {+ 1}\end{bmatrix}},{N_{TRN}^{N_{TX}} = 2}} & \left\lbrack {{Equation}\mspace{14mu} 17} \right\rbrack\end{matrix}$The OFDM TRN mapping matrix for N_(TX)=3 is defined as follows:

$\begin{matrix}{{P_{TRN} = \begin{bmatrix}{+ 1} & {- 1} & {+ 1} \\{+ 1} & {- w_{3}^{1}} & w_{3}^{2} \\{+ 1} & {- w_{3}^{2}} & w_{3}^{4}\end{bmatrix}},{w_{3} = {\exp\left( {{- j}\; 2\;{\pi/3}} \right)}},{N_{TRN}^{N_{TX}} = 3}} & \left\lbrack {{Equation}\mspace{14mu} 18} \right\rbrack\end{matrix}$The OFDM TRN mapping matrix for N_(TX)=4 is defined as follows:

$\begin{matrix}{{P_{TRN} = {P_{4 \times 4} = \begin{bmatrix}{+ 1} & {- 1} & {+ 1} & {+ 1} \\{+ 1} & {+ 1} & {- 1} & {+ 1} \\{+ 1} & {+ 1} & {+ 1} & {- 1} \\{- 1} & {+ 1} & {+ 1} & {+ 1}\end{bmatrix}}},{N_{TRN}^{N_{TX}} = 4}} & \left\lbrack {{Equation}\mspace{14mu} 19} \right\rbrack\end{matrix}$The OFDM TRN mapping matrix for N_(TX)=5, 6 is defined as follows:

$\begin{matrix}{{P_{TRN} = \begin{bmatrix}{+ 1} & {- 1} & {+ 1} & {+ 1} & {+ 1} & {- 1} \\{+ 1} & {- w_{6}^{1}} & w_{6}^{2} & w_{6}^{3} & w_{6}^{4} & {- w_{6}^{5}} \\{+ 1} & {- w_{6}^{2}} & w_{6}^{4} & w_{6}^{6} & w_{6}^{8} & {- w_{6}^{10}} \\{+ 1} & {- w_{6}^{3}} & w_{6}^{6} & w_{6}^{9} & w_{6}^{12} & {- w_{6}^{15}} \\{+ 1} & {- w_{6}^{4}} & w_{6}^{8} & w_{6}^{12} & w_{6}^{16} & {- w_{6}^{20}} \\{+ 1} & {- w_{6}^{5}} & w_{6}^{10} & w_{6}^{15} & w_{6}^{20} & {- w_{6}^{25}}\end{bmatrix}},{w_{6} = {\exp\left( {{- j}\; 2\;{\pi/6}} \right)}},{N_{TRN}^{N_{TX}} = 6}} & \left\lbrack {{Equation}\mspace{14mu} 20} \right\rbrack\end{matrix}$The OFDM TRN mapping matrix for N_(TX)=7, 8 is defined as follows:

${P_{TRN} = \begin{bmatrix}P_{4 \times 4} & P_{4 \times 4} \\P_{4 \times 4} & {- P_{4 \times 4}}\end{bmatrix}},{N_{TRN}^{N_{TX}} = 8}$

The descriptions above summarize what have been disclosed in Sections3.1.1 to 3.1.3, and it should be understood by those skilled in the artto which the present invention belongs that the descriptions given inSection 3.1.4 are included in the descriptions given in Sections 3.1.1to 3.1.3.

3.2. Method for Transmitting and Receiving Signals Including a TRNSubfield in the OFDM Mode

In one embodiment to which the present invention may be applied,transmission of a TRN field may be started by repeated transmission of aTRN subfield T times. At this time, the TRN subfields transmittedrepeatedly T times may be transmitted by using/based on the AntennaWeight Vector (AWV) used for transmission of the initial P TRNsubfields.

The T repeated transmission of the TRN subfield, which is the beginningof the TRN field, may be defined for providing a transition intervalbetween processing of the data and the TRN fields of a receiver.

According to the present invention, the T value may be determined basedon the value indicated by/included in the TRN Subfield Sequence Lengthfield of the EMDG Header-A field. As one example, when the TRN SubfieldSequence Length field value of the EMDG Header-A field is 0, the T valuemay be 2. Similarly, when the TRN Subfield Sequence Length field valueof the EMDG Header-A field is 1, the T value may be 1. Similarly, whenthe TRN Subfield Sequence Length field value of the EMDG Header-A fieldis 2, the T value may be 4.

Accordingly, before transmitting a TRN subfield per space-time streamincluded in the TRN field, the transmitter may transmit the TRN subfieldper space-time stream T times. In other words, the transmitted signalmay include the training subfield, wherein the training subfield istransmitted repeatedly T times after a data field based on informationindicated by/included in the header field, wherein T is a naturalnumber.

FIG. 39 is a flow diagram illustrating a method for transmitting signalsincluding a TRN field according to one embodiment of the presentinvention. In what follows, a TRN field may be interpreted as a conceptwhich includes time duration over which all of training subfields aretransmitted.

First, a transmitter (for example, STA) generates a training subfieldconfigured of/including a predetermined number of OFDM symbols includedin a transmitted signal S3910. At this time, the training subfield maybe configured for each space-time stream.

At this time, the training subfield per space-time stream may beconfigured by using/based on a basic training subfield per space-timestream configured of M (where M is a natural number) OFDM symbols basedon the information indicated by/included in the header field based onthe rule determined by the total number of space-time streams.

As one example, when the total number of space-time streams is 1, thetraining subfield per space-time stream may be configured as follows. Inwhat follows, OFDM_TRN_subfield_N denotes a training subfield withrespect to a space-time stream index N, and OFDM_TRN_basic_N denotes abasic training subfield with respect to the space-time stream index N.

-   -   OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −OFDM_TRN_basic_1]

As another example, when the total number of space-time streams is 2,the training subfield per space-time stream may be configured asfollows.

-   -   OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −OFDM_TRN_basic_1]    -   OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, OFDM_TRN_basic_2]

As yet another example, when the total number of space-time streams is3, the training subfield per space-time stream may be configured asfollows. In the mathematical equation given below, w₃=exp(−j*2*pi/3).

-   -   OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −OFDM_TRN_basic_1,        OFDM_TRN_basic_1]    -   OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, −w₃ ¹*OFDM_TRN_basic_2,        w₃ ²*OFDM_TRN_basic_2]    -   OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, −w₃ ³*OFDM_TRN_basic_3,        w₃ ⁴*OFDM_TRN_basic_3]

As yet another example, when the total number of space-time streams is4, the training subfield per space-time stream may be configured asfollows.

-   -   OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −OFDM_TRN_basic_1,        OFDM_TRN_basic_1, OFDM_TRN_basic_1]    -   OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, OFDM_TRN_basic_2,        −OFDM_TRN_basic_2, OFDM_TRN_basic_2]    -   OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, OFDM_TRN_basic_3,        OFDM_TRN_basic_3, −OFDM_TRN_basic_3]    -   OFDM_TRN_subfield_4=[−OFDM_TRN_basic_4, OFDM_TRN_basic_4,        OFDM_TRN_basic_4, OFDM_TRN_basic_4]

As still another example, when the total number of space-time streams is5, the training subfield per space-time stream may be configured asfollows. In the mathematical equation given below, w₆=exp(−j*2*pi/6).

-   -   OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −OFDM_TRN_basic_1,        OFDM_TRN_basic_1, OFDM_TRN_basic_1, OFDM_TRN_basic_1,        −OFDM_TRN_basic_1]    -   OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, −w₆ ¹*OFDM_TRN_basic_2,        w₆ ²*OFDM_TRN_basic_2, w₆ ³*OFDM_TRN_basic_2, w₆        ⁴*OFDM_TRN_basic_2, −w₆ ⁵*OFDM_TRN_basic_2]    -   OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, −w₆ ²*OFDM_TRN_basic_3,        w₆ ⁴*OFDM_TRN_basic_3, w₆ ⁶*OFDM_TRN_basic_3, w₆        ⁸*OFDM_TRN_basic_3 −w₆ ¹⁰*OFDM_TRN_basic_3]    -   OFDM_TRN_subfield_4=[OFDM_TRN_basic_4, −w₆ ³*OFDM_TRN_basic_4,        w₆ ⁶*OFDM_TRN_basic_4, w₆ ⁹*OFDM_TRN_basic_4, w₆        ¹²*OFDM_TRN_basic_4 −w₆ ¹⁵*OFDM_TRN_basic_4]    -   OFDM_TRN_subfield_5=[OFDM_TRN_basic_5, −w₆ ⁴*OFDM_TRN_basic_5,        w₆ ⁸*OFDM_TRN_basic_5, w₆ ¹²*OFDM_TRN_basic_5, w₆        ¹⁶*OFDM_TRN_basic_5 −w₆ ²⁰*OFDM_TRN_basic_5]

As a further example, when the total number of space-time streams is 5,the training subfield per space-time stream may be configured asfollows.

-   -   OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −OFDM_TRN_basic_1,        OFDM_TRN_basic_1, OFDM_TRN_basic_1, OFDM_TRN_basic_1,        −OFDM_TRN_basic_1]    -   OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, −w₆ ¹*OFDM_TRN_basic_2,        w₆ ²*OFDM_TRN_basic_2, w₆ ³*OFDM_TRN_basic_2, w₆        ⁴*OFDM_TRN_basic_2, −w₆ ⁵*OFDM_TRN_basic_2]    -   OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, −w₆ ²*OFDM_TRN_basic_3,        w₆ ⁴*OFDM_TRN_basic_3, w₆ ⁶*OFDM_TRN_basic_3, w₆        ⁸*OFDM_TRN_basic_3 −w₆ ¹⁰*OFDM_TRN_basic_3]    -   OFDM_TRN_subfield_4=[OFDM_TRN_basic_4, −w₆ ³*OFDM_TRN_basic_4,        w₆ ⁶*OFDM_TRN_basic_4, w₆ ⁹*OFDM_TRN_basic_4, w₆        ¹²*OFDM_TRN_basic_4 −w₆ ¹⁵*OFDM_TRN_basic_4]    -   OFDM_TRN_subfield_5=[OFDM_TRN_basic_5, −w₆ ⁴*OFDM_TRN_basic_5,        w₆ ⁸*OFDM_TRN_basic_5, w₆ ¹²*OFDM_TRN_basic_5, w₆        ¹⁶*OFDM_TRN_basic_5 −w₆ ²⁰*OFDM_TRN_basic_5]    -   OFDM_TRN_subfield_6=[OFDM_TRN_basic_6, −w₆ ⁵*OFDM_TRN_basic_6,        w₆ ¹⁰*OFDM_TRN_basic_6, w₆ ¹⁵*OFDM_TRN_basic_6, w₆        ²⁰*OFDM_TRN_basic_6 −w₆ ²⁵*OFDM_TRN_basic_6]

As an additional example, when the total number of space-time streams is7, the training subfield per space-time stream may be configured asfollows.

-   -   OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −OFDM_TRN_basic_1,        OFDM_TRN_basic_1, OFDM_TRN_basic_1, OFDM_TRN_basic_1,        −OFDM_TRN_basic_1, OFDM_TRN_basic_1 OFDM_TRN_basic_1]    -   OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, OFDM_TRN_basic_2,        −OFDM_TRN_basic_2, OFDM_TRN_basic_2, OFDM_TRN_basic_2,        OFDM_TRN_basic_2, −OFDM_TRN_basic_2, OFDM_TRN_basic_2]    -   OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, OFDM_TRN_basic_3,        OFDM_TRN_basic_3, −OFDM_TRN_basic_3, OFDM_TRN_basic_3,        OFDM_TRN_basic_3, OFDM_TRN_basic_3, −OFDM_TRN_basic_3]    -   OFDM_TRN_subfield_4=[−OFDM_TRN_basic_4, OFDM_TRN_basic_4,        OFDM_TRN_basic_4, OFDM_TRN_basic_4, −OFDM_TRN_basic_4,        OFDM_TRN_basic_4, OFDM_TRN_basic_4, OFDM_TRN_basic_4]    -   OFDM_TRN_subfield_5=[OFDM_TRN_basic_5, −OFDM_TRN_basic_5,        OFDM_TRN_basic_5, OFDM_TRN_basic_5, −OFDM_TRN_basic_5,        OFDM_TRN_basic_5, −OFDM_TRN_basic_5, −OFDM_TRN_basic_5]    -   OFDM_TRN_subfield_6=[OFDM_TRN_basic_6, OFDM_TRN_basic_6,        −OFDM_TRN_basic_6, OFDM_TRN_basic_6, −OFDM_TRN_basic_6,        −OFDM_TRN_basic_6, OFDM_TRN_basic_6, −OFDM_TRN_basic_6]    -   OFDM_TRN_subfield_7=[OFDM_TRN_basic_7, OFDM_TRN_basic_7,        OFDM_TRN_basic_7, −OFDM_TRN_basic_7, −OFDM_TRN_basic_7,        −OFDM_TRN_basic_7, −OFDM_TRN_basic_7, OFDM_TRN_basic_7]

As yet another additional example, when the total number of space-timestreams is 8, the training subfield per space-time stream may beconfigured as follows.

-   -   OFDM_TRN_subfield_1=[OFDM_TRN_basic_1, −OFDM_TRN_basic_1,        OFDM_TRN_basic_1, OFDM_TRN_basic_1, OFDM_TRN_basic_1,        −OFDM_TRN_basic_1, OFDM_TRN_basic_1, OFDM_TRN_basic_1]    -   OFDM_TRN_subfield_2=[OFDM_TRN_basic_2, OFDM_TRN_basic_2,        −OFDM_TRN_basic_2, OFDM_TRN_basic_2, OFDM_TRN_basic_2,        OFDM_TRN_basic_2, −OFDM_TRN_basic_2, OFDM_TRN_basic_2]    -   OFDM_TRN_subfield_3=[OFDM_TRN_basic_3, OFDM_TRN_basic_3,        OFDM_TRN_basic_3, −OFDM_TRN_basic_3, OFDM_TRN_basic_3,        OFDM_TRN_basic_3, OFDM_TRN_basic_3, −OFDM_TRN_basic_3]    -   OFDM_TRN_subfield_4=[−OFDM_TRN_basic_4, OFDM_TRN_basic_4,        OFDM_TRN_basic_4, OFDM_TRN_basic_4, −OFDM_TRN_basic_4,        OFDM_TRN_basic_4, OFDM_TRN_basic_4, OFDM_TRN_basic_4]    -   OFDM_TRN_subfield_5=[OFDM_TRN_basic_5, −OFDM_TRN_basic_5,        OFDM_TRN_basic_5, OFDM_TRN_basic_5, −OFDM_TRN_basic_5,        OFDM_TRN_basic_5, −OFDM_TRN_basic_5, −OFDM_TRN_basic_5]    -   OFDM_TRN_subfield_6=[OFDM_TRN_basic_6, OFDM_TRN_basic_6,        −OFDM_TRN_basic_6, OFDM_TRN_basic_6, −OFDM_TRN_basic_6,        −OFDM_TRN_basic_6, OFDM_TRN_basic_6, −OFDM_TRN_basic_6]    -   OFDM_TRN_subfield_7=[OFDM_TRN_basic_7, OFDM_TRN_basic_7,        OFDM_TRN_basic_7, −OFDM_TRN_basic_7, −OFDM_TRN_basic_7,        −OFDM_TRN_basic_7, −OFDM_TRN_basic_7, OFDM_TRN_basic_7]    -   OFDM_TRN_subfield_8=[−OFDM_TRN_basic_8, OFDM_TRN_basic_8,        OFDM_TRN_basic_8, OFDM_TRN_basic_8, OFDM_TRN_basic_8,        −OFDM_TRN_basic_8, −OFDM_TRN_basic_8, −OFDM_TRN_basic_8]

At this time, based on the information indicated by/included in theheader field, the basic training subfield per space-time stream may beconfigured of one, two, or four OFDM symbols.

At this time, one OFDM symbol included in the one, two, or four OFDMsymbols may include a guard interval with a length of 72.72 ns or cyclicprefix (CP).

Also, the header field may include an Enhanced Directional Multi Gigabit(EDMG) training subfield sequence length field which indicates/includinginformation on the OFDM symbol length of the basic training subfield perspace-time stream.

More specifically, when the EDMG training subfield sequence length fieldindicates 0, the basic training subfield per space-time stream may beconfigured of two OFDM symbols; when the EDMG training subfield sequencelength field indicates 1, the basic training subfield per space-timestream may be configured of four OFDM symbols; and when the EDMGtraining subfield sequence length field indicates 2, the basic trainingsubfield per space-time stream may be configured of one OFDM symbol.

In the composition above, the basic training subfield per space-timestream may be configured of a sequence with a different length in thefrequency domain according to the number of contiguous channels overwhich the signal is transmitted.

As one example, when the number of contiguous channels over which thesignal is transmitted is 1, the basic training subfield per space-timestream may be configured of a sequence with a length of 355 in thefrequency domain. At this time, a 512-point IDFT may be applied to thesequence.

As another example, when the number of contiguous channels over whichthe signal is transmitted is 2, the basic training subfield perspace-time stream may be configured of a sequence with a length of 773in the frequency domain. At this time, a 1024-point IDFT may be appliedto the sequence.

As yet another example, when the number of contiguous channels overwhich the signal is transmitted is 3, the basic training subfield perspace-time stream may be configured of a sequence with a length of 596in the frequency domain. At this time, a 1536-point IDFT may be appliedto the sequence.

As still another example, when the number of contiguous channels overwhich the signal is transmitted is 4, the basic training subfield perspace-time stream may be configured of a sequence with a length of 805in the frequency domain. At this time, a 2048-point IDFT may be appliedto the sequence.

Next, the transmitter transmits a signal including the training subfieldper space-time stream generated as described above and the header fieldS3920. At this time, the transmitter may transmit the training subfield(per space-time stream) subsequent to the data field included in thesignal repeatedly T times (where T is a natural number) based on theinformation indicated by/included in the header field. Accordingly, thetransmitted signal includes the training subfield (per space-timestream), wherein the training subfield is transmitted repeatedly T timesafter a data field based on information indicated by/included in theheader field, wherein T is a natural number.

At this time, as described in detail above, the T value may bedetermined by the information (namely the information indicatedby/included in the EDMG training subfield sequence length fieldincluding in the EDMG header field) indicated by/included in the headerfield.

As one example, when the EDMG training subfield sequence length fieldindicates 0, the basic training subfield per space-time stream may beconfigured of two OFDM symbols, and the T value may be set to 2.

As another example, when the EDMG training subfield sequence lengthfield indicates 1, the basic training subfield per space-time stream maybe configured of four OFDM symbols, and the T value may be set to 1.

As yet another example, when the EDMG training subfield sequence lengthfield indicates 2, the basic training subfield per space-time stream maybe configured of one OFDM symbol, and the T value may be set to 4.

Through the composition as described above, the time duration over whichthe training subfield per space-time stream is actually transmittedrepeatedly T times may be kept to a fixed value irrespective of thevalue indicated by/included in the EDMG training subfield sequencelength field.

At this time, when the signal is transmitted through a plurality ofchannels, the transmitter may transmit the signal through thecorresponding space-time stream within a plurality of channels.

In response to the transmission, first, the receiver receives a headerfield included in the transmitted signal. Next, the receiver receivesthe signal by switching processing between a data field and a trainingfield during a period within a period during which the signal istransmitted, wherein the training subfield is transmitted repeatedly Ttimes after a data field based on the information indicated by/includedin the header field during the period, wherein the training subfield isconfigured of/includes a predetermined number of Orthogonal FrequencyDivision Multiplexing (OFDM) symbols, wherein the T is a natural number.

At this time, as described above, the time period over which thetraining subfield per space-time stream is actually transmittedrepeatedly T times may be kept to a fixed value irrespective of thevalue indicated by/included in the EDMG training subfield sequencelength field.

4. Device Configuration

FIG. 40 is a diagram illustrating a device for implementing theabove-described method.

A wireless device 100 of FIG. 40 may correspond to an STA that transmitsa signal described in the above description, and a wireless device 150may correspond to an STA that receives a signal described in the abovedescription.

In this case, the station transmitting the signal may correspond to aPCP/AP or an 11ay terminal supporting an 11ay system, and the stationreceiving the signal may correspond to a legacy terminal (e.g., 11adterminal) that does not support the 11ay system as well as a PCP/AP oran 11ay terminal supporting the 11ay system.

Hereinafter, for convenience of description, the STA transmitting asignal is referred to as a transmitting device 100, and the STAreceiving a signal is referred to as a receiving device 150.

The transmitting device (100) may include a processor (110), a memory(120), and a transmitting/receiving unit (130), and the receiving device(150) may include a processor (160), a memory (170), and atransmitting/receiving unit (180). The transmitting/receiving unit (130,180) transmits/receives a radio signal and may be operated in a physicallayer of IEEE 802.11/3GPP, and so on. The processor (110, 160) may beoperated in the physical layer and/or MAC layer and may be operativelyconnected to the transmitting/receiving unit (130, 180).

The processor (110, 160) and/or the transmitting/receiving unit (130,180) may include application-specific integrated circuit (ASIC), otherchipset, logic circuit and/or data processor. The memory (120, 170) mayinclude read-only memory (ROM), random access memory (RAM), flashmemory, memory card, storage medium and/or other storage unit. When theembodiments are executed by software, the techniques (or methods)described herein can be executed with modules (e.g., processes,functions, and so on) that perform the functions described herein. Themodules can be stored in the memory (120, 170) and executed by theprocessor (110, 160). The memory (120, 170) can be implemented (orpositioned) within the processor (110, 160) or external to the processor(110, 160). Also, the memory (120, 170) may be operatively connected tothe processor (110, 160) via various means known in the art.

As described above, the detailed description of the preferred exemplaryembodiment of the present invention is provided so that anyone skilledin the art can implement and execute the present invention. In thedetailed description presented herein, although the present invention isdescribed with reference to the preferred exemplary embodiment of thepresent invention, it will be understood by anyone having ordinaryskills in the art that diverse modifications, alterations, andvariations can be made in the present invention. Therefore, the scopeand spirit of the present invention will not be limited only to theexemplary embodiments of the present invention set forth herein. Thus,it is intended to provide the broadest scope and spirit of the appendedclaims of the present invention that are equivalent to the disclosedprinciples and novel characteristics of the present invention.

INDUSTRIAL APPLICABILITY

Although the present invention has been described in detail under theassumption that the present invention can be applied to an IEEE 802.11based wireless LAN (WLAN) system, the present invention will not belimited only to this. It will be understood that the present inventioncan be applied to diverse wireless systems capable of performing datatransmission based on channel bonding by using the same method aspresented herein.

What is claimed is:
 1. A method for transmitting, by a first station(STA), a signal to a second STA in a Wireless Local Area Network (WLAN)system, comprising: generating a training subfield including at leastone Orthogonal Frequency Division Multiplexing (OFDM) symbol, wherein:the training subfield is configured based on a basic training subfield,the basic training subfield is configured for at least one space timestream, the basic training subfield includes a first sequence, a zerosequence being contiguous to the first sequence, and a second sequencebeing contiguous to the zero sequence, the first and second sequenceshave a same length, and the zero sequence is configured based on {0, 0,0}; and transmitting the signal including a header field, a data fieldand a training field to the second STA, wherein: the training fieldstarts with T repetitions of the training subfield, when the trainingsubfield is composed of one basic training subfield, T is 4, when thetraining subfield is composed of two basic training subfields, T is 2,and when the training subfield is composed of four basic trainingsubfields, T is
 1. 2. The method of claim 1, wherein when the signal istransmitted over a 2.16 GHz channel, a length of the first sequence orthe second sequence is set to 176 symbols, and when the signal istransmitted over a 4.32 GHz channel, a length of the first sequence orthe second sequence is set to 385 symbols.
 3. The method of claim 1,wherein when the signal is transmitted over a 6.48 GHz channel, a lengthof the first sequence or the second sequence is set to 595 symbols, andwhen the signal is transmitted over a 8.64 GHz channel, a length of thefirst sequence or the second sequence is set to 804 symbols.
 4. Themethod of claim 1, wherein the basic training subfield is configured fora maximum of eight space time streams.
 5. The method of claim 1, whereinone OFDM symbol included in the basic training subfield includes a guardinterval with a length of 72.72 ns or cyclic prefix (CP).
 6. A methodfor receiving, by a first station (STA), a signal from a second STA in aWireless Local Area Network (WLAN) system, comprising: receiving aheader field, a data field and a training field included in the signal;and decoding the signal, wherein: the training field starts with Trepetitions of a training subfield, the training subfield is configuredbased on a basic training subfield, the basic training subfield isconfigured for at least one space time stream, the basic trainingsubfield includes a first sequence, a zero sequence being contiguous tothe first sequence, and a second sequence being contiguous to the zerosequence, the first and second sequences have a same length, the zerosequence is configured based on {0, 0, 0}, the header field includesinformation related to a length of the training subfield, when thetraining subfield is composed of one basic training subfield, T is 4,when the training subfield is composed of two basic training subfields,T is 2, and when the training subfield is composed of four basictraining subfields, T is
 1. 7. A first station in a Wireless Local AreaNetwork (WLAN) system, comprising: a transceiver having one or moreRadio Frequency (RF) chains and transmitting signals to a secondstation; and a processor coupled to the transceiver and configured to:generate a training subfield including at least one Orthogonal FrequencyDivision Multiplexing (OFDM) symbol, wherein: the training subfield isconfigured based on a basic training subfield, the basic trainingsubfield is configured for at least one space time stream, the basictraining subfield includes a first sequence, a zero sequence beingcontiguous to the first sequence, and a second sequence being contiguousto the zero sequence, the first and second sequences have a same length,and the zero sequence is configured based on {0, 0, 0}; and control thetransceiver to transmit a signal including a header field, a data fieldand a training field to the second station, wherein: the header fieldincludes information related to a length of the training subfield, thetraining field starts with T repetitions of the training subfield, whenthe training subfield is composed of one basic training subfield, T is4, when the training subfield is composed of two basic trainingsubfields, T is 2, and when the training subfield is composed of fourbasic training subfields, T is
 1. 8. The first station of claim 7,wherein when the signal is transmitted over a 2.16 GHz channel, a lengthof the first sequence or the second sequence is set to 176 symbols, andwhen the signal is transmitted over a 4.32 GHz channel, a length of thefirst sequence or the second sequence is is set to 385 symbols.
 9. Thefirst station of claim 7, wherein when the signal is transmitted over a6.48 GHz channel, a length of the first sequence or the second sequenceis set to 595 symbols, and when the signal is transmitted over a 8.64GHz channel, a length of the first sequence or the second sequence isset to 804 symbols.
 10. The first station of claim 7, wherein the basictraining subfield is configured for a maximum of eight space timestreams.
 11. The first station of claim 7, wherein one OFDM symbolincluded in the basic training subfield includes a guard interval with alength of 72.72 ns or cyclic prefix (CP).